05/305554

12/24/1974

11/10/1972

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Shionogi & Co., Ltd. (Osaka, JA)

514/26

A61K31/335; C07J17/00; A61K27/14

424/182

French, Henry A.

Wenderoth, Lind & Ponack

This is a division of application Ser. No. 18,337, filed Mar. 10, 1970, now U.S. Pat. No. 3,745,156.

What we claim is

1. A process for the treatment of human, poultry or veterinary heart diseases which comprises the administration of a medicament comprising a pharmaceutically effective amount of a cardiotonic compound of following formula ##SPC7##

2. A process according to claim 1 which comprises administering a medicament comprising 0.1 μg to 10 mg per day per kilogram of body weight of a cardiotonic compound selected from the group consisting of

3. beta.-(β-D-digitoxosyl)oxy-17β-(3-furyl)-5β,14β-andro stane-12β,14-diol,

4. beta.-(β-D-digitoxosyl)oxy-17β-(3-furyl)-5β,14β-andro stane-14,16β-diol,

5. beta.-(β-D-digitoxosyl)oxy-17β-(3-furyl)-5β,14β-andro stane-12β,14,16β-triol,

6. beta.-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-5β,14.bet a.-androstane-12β,14-diol,

7. beta.-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-5β,14.bet a.-androstane-12β,14,16β-triol,

8. A process according to claim 1 which comprises administering a medicament comprising about 0.2 to 8 mg of a cardiotonic compound selected from the group consisting of

9. beta.-(β-D-digitoxosyl)oxy-17β-(3-furyl)-5β,14β-andro stane-12β,14-diol,

10. beta.-(β-D-digitoxosyl)oxy-17β-(3-furyl)5β,14β-andros tane-14,16β-diol,

11. beta.-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3-fu ryl)-5β,14β-androstane-12β,14-diol,

12. beta.-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3-fu ryl)-5β,14β-androstane-14,16β-diol,

13. A process according to claim 1 which comprises administering a medicament comprising about 0.2 to 8 mg of 3β-(β-D-digitoxosyl)oxy-17β-(3-furyl)-5β,14β-andr ostane-14,16β-diol or 3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3-f uryl)-5β,14β-androstane-14,16β-diol, in combination with a pharmaceutical carrier.

14. A process according to claim 1 which comprises administering a medicament comprising about 0.2 to 8 mg of 3β-(β-D-digitoxosyl)oxy-17β-(3-furyl)-5β,14β-andr ostane-12β,14-diol or 3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3-f uryl)-5β,14β-androstane-12β,14-diol, in combination with a pharmaceutical carrier.

The present invention relates to a novel process for partial hydrolysis of glycosides of 2-deoxy-sugar, and some glycosides of 2-deoxy-sugar, and preparations containing the products of the process of the present invention.

The process of the present invention is a selective method of hydrolysis which does not affect on a 2-deoxy-glycosyl residue when it is not present at the terminal position of the glycoside linkage.

Numerous reports are found on the selective hydrolysis of glycosides of 2-deoxy-sugar. Representatives of them include report of A. Stoll (Helvetica Chimica Acta, Vol. 18, 120 (1935)) which describes selective enzymatic hydrolysis of digilanides to remove glucose unit from the glycoside chain; and reports of F. Kaiser, et al. (Annalen der Chemie, Vol. 603, page 75 (1957)) which describes nonselective acid hydrolysis of cardenolide tridigitoxosides with acids followed by repeated tedious partition chromatography. However, these methods are insufficient for preparative or industrial use, because of their non-selectiveness, lower yield, complexed techniques, large volume of reaction mixture, similarity of physical constants of the products and other many deficiencies to be cited. In the course of investigation of acetates of digitoxin and gitoxin, the present inventor intended to determine which of the hydroxyl group in the glycosides were acetylated. He should remove sugar residue one by one from terminal and he conveived to use the glycol cleavage reaction for this purpose in order to increase selectivity to hydrolysis of the residue to be removed. He then extended the method to a general procedure for selective hydrolysis of the glycosides containing 2-deoxy-sugar units as the sugar moiety.

The process of the present invention is a method for selective hydrolysis of glycosides having 2-deoxy-sugar unit in the molecule which is characterized (1) by increasing of sensitivity for hydrolysis of the specified sugar unit to be removed by the result of glycol cleavage reaction; (2) by providing selectivity with utilization of the fact that 2-deoxy-sugar unit which is not located at the terminal position of the glycoside linkage is not susceptible of the reaction of the process of the present invention; (3) by higher yield; (4) by unequivocal chemical procedure; and (5) by mild and easily handled reaction course.

Methods for hydrolysis of glycosides by way of similar reaction techniques are presented in some of the known literatures, e.g. F. Smith et al.: Journal of the American Chemical Society, Vol. 81, page 2176 (1959); E. L. Jackson and C. S. Hudson: Journal of the American Chemical Society, Vol. 58, page 378 (1936); I. J. Goldstein et al.: Methods in Carbohydrate Chemistry, Vol. V, page 361 (1965); E. L. Jackson: Organic Reactions, Vol. II, page 341 (1944); Dugan: Canadian Journal of Chemistry: Vol. 43, page 2033 (1965); P.P. Regna: Journal of the American Chemical Society, Vol. 69, page 246 (1947); and references cited in these literatures. These methods however do not relate to glycosides of 2-deoxy-sugars and further they direct to degradative hydrolysis of glycosides resistant to normal hydrolysis conditions. Hence, the reaction conditions are rather drastic and there is no intention for selective hydrolysis in respect of the sugar units. In other words, the present invention is an extension of these methods into the field of 2-deoxy-sugar and to the field of cardenolide glycosides and their analogues.

The process of the present invention comprises the first step in which the glycosides are subjected to glycol cleavage reaction to afford dialdehyde or acetals thereof, followed by optional reduction of the product to afford dimethylol; and the second step in which the product of the first step is subjected to hydrolysis under extremely mild condition. The mild condition allows possible existence of unstable group in the other part of the molecule of the glycosides.

The starting materials of the process of the present invention are the glycosides of the formula: ##SPC2##

wherein X represents an oxygen containing hydrocarbon ring group, R ₁ and R ₂ each represents a hydrogen atom, hydroxyl group or acyloxy group, R _m represents a hydrogen atom or acyl group same or different for each sugar unit and n is an integer 1 or more.

As for the oxygen containing hydrocarbon ring represented by X, it is exemplified 2- and 3-furyl group and α, β and γ-butenolide residue, butanolide group and the like. As for the acyl group represented by R _m and that of acyloxy group represented by R ₁ and R ₂ , there is exemplified alkanoyl groups e.g. formyl, acetyl, propionyl, butyryl, enanthoyl, stearoyl, trimethylacetyl, tert-butylacetyl, cyclohexylcarbonyl, apocamphane-1-carbonyl, adamantane-carbonyl, cyclopentanealkanoyl, and the like; unsaturated aliphatic acyl groups e.g. crotenyl, ethynyl-acetyl, and the like; substituted aliphatic acyl groups e.g. haloacetyl, glycyl, lactyl, hemisuccinyl, phenylpropionyl, cinnamoyl, optionally substituted phenoxyacetyl, etc; optionally substituted aromatic acyl groups e.g. benzoyl, nitro-benzoyl, methoxybenzoyl, methylbenzoyl, halobenzoyl, naphthalin-carbonyl, nicotinyl, furoyl, and the like; or inorganic acyl groups e.g. carbonic, sulfuric, phosphoric acyl groups and the like.

Representatives of the starting materials of the process of the present invention involve:

digitoxin,

digoxin,

gitoxin,

diginatin,

digitoxigenin-bisdigitoxoside,

digoxigenin-bisdigitoxoside,

gitoxigenin-bisdigitoxoside,

diginatigenin-bisdigitoxoside,

3β-(β-D-digitoxosyl-β-D-digitoxosyl-β-D-digitoxosyl) oxy -17β-(3-furyl)-5β,14β-androstan-14-ol,

3β-(β-D-digitoxosyl-β-D-digitoxosyl-β-D-digitoxosyl) oxy -17β-(3-furyl)-5β,14β-androstane-12β,14-diol,

3β-(β-D-digitoxosyl-β-D-digitoxosyl-β-D-digitoxosyl) oxy -17β-(3-furyl)-5β,14β-androstane-14,16β-diol,

3β-(β-D-digitoxosyl-β-D-digitoxosyl-β-D-digitoxosyl) oxy -17β-(3-furyl)-5β,14β-androstane-12β,14,16β-triol,

3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3 -fu ryl)-5β,14β-androstan-14-ol,

3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3 -fu ryl)-5β,14β-androstane-12β,14-diol,

3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]-oxy-17β-( 3-f uryl)-5β,14β-androstane-14,14β-diol,

3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3 -fu ryl)-5β,14β-androstane-12β,14,16β-triol,

and esters thereof with the proviso that the terminal digitoxose residue has two free hydroxyl groups.

The first step of the process of the present invention comprises glycol cleavage of the starting materials mentioned above at the terminal sugar unit, followed by optional reduction. The reaction of the first step is represented by the reaction scheme: ##SPC3##

The compound of the partial formula (1) react with glycol cleaving agents more smoothly than the corresponding 2-hydroxylated sugar compounds. The products are "dialdehyde" (2) and acetals thereof represented e.g. by the partial formulae (3) and (4). The dialdehyde (2) as well as acetals thereof are reduced to "dimethylol" (5) by the action of ordinary reducing agent in high yield.

The said glycol cleaving agent may be chromic acid, permanganates, nitric acid, persulfuric acid, cuppric hydroxide, bismuthates, manganese acetate, iodosobenzene alkanoates, osmium tetra-oxide, ruthenium tetroxide, lead tetraacetate, periodates, periodic acid and the like, in which lead tetraacetate, periodic acid and periodates are preferable. The cleaving agents are used in various solvents. For example, they may be hydrocarbons e.g. petroleum benzine, petroleum ether, heptane, hexane, benzene, toluene, xylene, cyclo-hexane, etc.; halogenated hydrocarbons e.g. carbon tetra-chloride, chloroform, methylene chloride, dichloroethane, tetrachloroethane, etc.; ethers e.g. diethyl ether, methyl butyl ether, tetrahydrofuran, tetrahydropyran, dioxane, ethylene glycol ethers, etc.; esters e.g. ethyl acetate, butyl acetate, etc.; ketones e.g. actone, methyl ethyl ketone, cyclohexanone, etc.; alcohols e.g. methanol, ethanol, butanol, octanol, etc.; carboxylic acids e.g. acetic acid, propionic acid, formic acid, etc.; bases e.g. pyridine, collidine, quinoline, etc.; and other solvents e.g. dimethylformamide, dimethylsulfoxide, water, etc., and mixture thereof. Generally, lead tetraacetate is used in non-polar solvents and periodic acid and periodates are used in polar solvents. If required, other solvents may be added thereto in order to dissolve the reactants. In the cases of periodates or periodic acid being used as the glycol cleaving agent and the solvent used being dilute alcohol, one of the product, salts of iodic acid separates as crystals in the medium and may be removed by mere filtration. Bases may be added to the reaction medium to neutralize acidic product. The reaction may be carried out at lowered or elevated temperatures. The amount of the glycol cleaving agent to the starting material are preferably 1 to 5 mole equivalents, although more reagent may be used without wrong results. The products are isolated in per se conventional methods e.g. dilution, concentration, extraction, filtration, etc., and are purified by conventional methods e.g. recrystallization, chromatography, etc. The products may be subjected to the process of the next step without further purification. The products thus obtained are dialdehyde of the partial formula (2) or acetals thereof e.g those represented by formulae (3) and (4). The said reducing agents for optional following reduction are those capable of reducing dialdehyde of the partial formula (2) or acetals thereof represented by e.g. partial formulae (3) and (4) to give dimethylol of the partial formula (5), provided that they do not exert irreversible changes in the other part of the substrate molecule. Representatives of preferable reducing agents for the process are metal hydrides, for example boron hydride compounds e.g. potassium borohydride, sodium borohydride, lithium borohydride, alkylboron hydrides, alkyl-boron hydrides, boron hydride, pyridine borane, alkylamine boranes, etc., aluminum hydride complexes e.g. lithium aluminum hydride, lithium alkylaluminum hydrides, lithium alkoxyaluminum hydrides, sodium aluminum hydride, alkyl-aluminum hydrides, alkoxyaluminum hydrides, etc., catalytic hydrogenations over various catalysts e.g. cobalt-cupper chromite, ruthenium-charcoal, palladium charcoal, palladium calcium carbonate, etc., Meerwein-Pondorf reduction, Meerwein-Schmidt reduction, and the like. The reduction may be carried out in a solvent e.g. hydrocarbons, halogented hydrocarbons, ethers, alcohols, esters, carboxylic acids, bases, water, etc., at elevated or lowered temperature. Optional character of reduction in the process of the present invention necessitates amount of the reducing agent used over a range from 0 to 1 mole equivalent or more. Preferable result is obtained when the reducing agent is 1 to 10 mole equivalents of e.g. sodium borohydride. The products thus prepared may be isolated in per se conventional methods e.g. decomposition of adduct, precipitation by addition of insoluble solvents, filtration, dilution, extraction, washing, drying, evaporation of solvents, absorption, elusion, etc., or their combination. The alternate process through reduction is in effect equivalent to direct hydrolysis to the dialdehyde (2) or acetals thereof e.g. compounds of partial formulae (3) and (4), and has superiority to the latter that the former shows less by-products product, higher purity of the product, easily purified, higher yield, and so on, irrespective of use of expensive reducing agent.

The second step of the process of the present invention comprises hydrolysis of the products of the first step. The reaction of the second step is represented by the reaction scheme: ##SPC4##

The dialdehyde (2) or acetals thereof e.g. (3) and (4), and the dimethylol (5) are hydrolyzed by action of various hydrolyzing agents more smoothly than the corresponding 2-nor compounds derived from 2-hydroxylated sugar units. The known methods applying the methods to 2-hydroxylated sugar require carrying out the reaction under stronger condition than that of the process of this invention. For example, the hydrolysis condition of Goldstein is 0.1 - 0.5 N hydrochloric acid for 6 - 8 hours at room temperature; that of Dugan is heating with 5 percent potassium hydroxide; and that of kubota (Tetrahedron, Vol. 24, page 675 (1968)) is refluxing with 3 % potassium hydroxide in ethanol for 1 hour and refluxing at 60°C with 0.1 % toluene-p-sulfonic acid in dioxane for 30 minutes. Under these conditions, sensitive groups e.g. 2-deoxy-sugar units 14-hydroxyl group, 17-unsaturated oxa ring, etc., showed various irreversible changes e.g. formation of iso-cardenolides, hydrolysis at undesired position, dehydration, etc. When the hydrolysis was carried out with 0.0065 N hydrochloric acid at room temperature, or 0.1 % potassium hydrogen carbonate at room temperature, the compounds (2), (3), (4) and (5) are hydrolyzed in a short time to obtain the compounds of the partial formula (6). Under the same conditions, the dialdehyde, acetals thereof or dimethylol derived from 2-hydroxylated terminal sugar unit, i.e. those derived from Purpurea glycoside A by reaction with sodium periodate, is not hydrolyzed and the starting material is recovered unchanged. The reactivity of the compounds to hydrolysis are in the order dimethylol, dialdehyde and dimethylol diacetate from higher to lower. From these data, it is concluded that in the case of dimethylol, some participation of free neighbouring hydroxyl group to reaction center is occuring. Higher reactivity of dialdehyde over dimethylol diacetate is presumed to be result of existence of carbonyl group at β-position from the reaction center to be hydrolyzed. The said hydrolysis of this step may be effected by the action of a reagent capable of decomposition of acetals recovering constituent alcohols. The reagent for reaction of this step may be acids, bases or other reagents of equivalent effect e.g. a carbonyl reagent which converts a β-oxygenated-carbonyl compound into an α,β-unsaturated oxo compound or an acetal into an alcohol and carbonyl bound with the ketone reagent. The said acids may be an acids ranging from weak acids e.g. phenols, aromatic or aliphatic carboxylic acids, silica gel, acid salts e.g. sodium hydrogen sulfate, pyridine sulfate, ammonium chloride, etc., to strong acids e.g. hydrochloric acid, nitric acid, phosphoric acid, perchloric acid, etc. The said bases may be bases ranging from weak bases e.g. alumina, calcium carbonate, potassium hydrogen carbonate, sodium hydrogen carbonate, lithium hydrogen carbonate, sodium acetate, potassium acetate, potassium carbonate, sodium carbonate, lithium carbonate, ammonia, pyridine, trialkylamines, etc., to strong bases e.g. potassium hydroxide, sodium hydroxide, lithium hydroxide, tetraalkylammonium hydroxides, etc. The said carbonyl reagents may be hydrazine, phenylhydrazine, 2,4-dinitrophenylhydrazine, carbazide, hydroxylamine, and the like. Those reagents for hydrolysis may be brought into contact with the starting materials of this step in the presence of a solvents e.g. water and organic solvents. Preferable concentration of the acids or bases may be 0.0001 - 30 % to the solvents. Preferable results have been obtained in the case of 0.1 - 0.0001 N mineral acid or treatment in an acidic medium of pH 1 - 4 at room temperature for 0.5 to 48 hours. Higher temperature may shorten the reaction period. The products of this step may be obtained by a conventional method e.g. precipitation, filtration, dilution, extraction, washing, drying, absorption, elusion, and the like or combinations thereof, followed by optional purification by e.g. chromatography, recrystallization, etc. In the process of the present invention, preferable results have been obtained in the cases of hydrolysis of the compounds of the partial formula (2) with acids, bases or ketone reagents, and in the cases of hydrolysis of the compounds of the partial formula (5) with acids.

The compounds prepared by the process of the present invention are the compounds of the formula: ##SPC5##

wherein X, R ₁ , R ₂ , R _m and n have the same significances as defined above.

Representatives of the products of the process of the present invention involve:

digitoxigenin-bisdigitoxoside,

digoxigenin-bisdigitoxoside,

gitoxigenin-bisdigitoxoside,

diginatigenin-bisdigitoxoside,

digitoxigenin-monodigitoxoside,

digoxigenin-monodigitoxoside,

gitoxigenin-mondigitoxoside,

diginatigenin-monodigitoxoside,

3β-[4-O-(β-D-digitoxosyl)-β-D-digittoxosyl]oxy-17β-( 3-f uryl)-5β,14β-androstan-14-ol

3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3 -fu ryl)-5β,14β-androstane-12β,14-diol,

3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3 -fu ryl)-5β,14β-androstane-14,16β-diol,

3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3 -fu ryl)-5β,14β-androstane-12β,14,16β-triol,

3β-(β-D-digitoxosyl)oxy-17β-(3-furyl)-5β,14β-andro stan-14-ol,

3β-(β-D-digitoxosyl)oxy-17β-(3-furyl)-5β,14β-andro stane-12β,14-diol,

3β-(β-D-digitoxosyl)oxy-17β-(3-furyl)-5β,14β-andro stane-14,16β-diol,

3β-(β-D-digitoxosyl)oxy-17β-(3-furyl)-5β,14β-andro stane-12β,14,16β-triol,

and esters thereof.

The first eight compounds cited above are literary known compounds of higher cardiotonic activity, but because of complexed process of preparation, they have not been utilized for practical purposes. The latter eight compounds and esters thereof are novel, safe, mild and strong cardiotonic and duretic compounds of the present invention. Both of them are useful as pharmaceutical agent in the treatment of heart diseases for human or veterinary use, in the forms of pharmaceutical composition containing an effective amount of the compounds and a pharmaceutically acceptable carrier.

The novel compounds of the present invention are represented by the general formula: ##SPC6## wherein R and 4' each represents a hydrogen atom or hydroxyl group and at least one of R and R' is hydroxyl; n' represents an integer 1 or 2 and lower alkanoates thereof. The aglycone part of these compounds is a group derived from 17β-(3-furyl)-5β,14β-androstane-3β,12β,14-triol, 17β-(3-furyl)-5β,14β-androstane-3β,14,16β-triol or 17β-(3-furyl)-5β,14β-androstane-3β,12β,14,16.b eta.-tetrol by removing a hydrogen atom from the hydroxyl group at position 3. The sugar part of these compounds is β-D-digitoxosyl group or 4-O-(β-D-digitoxosyl)-β-D-digitoxosyl group.

Representatives of the compounds of the present invention involve:

3β-(β-D-digitoxosyl)oxy-17β-(3-furyl)-5β,14β-andro stane-12β,14-diol,

3β-(β-D-digitoxosyl)oxy-17β-(3-furyl)-5β,14β-andro stane-14,16β-diol,

3β-(β-D-digitoxosyl)oxy-17β-(3-furyl)-5β,14β-andro stane-12β,14,16β-triol,

3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3 -fu ryl)-5β,14β-androstan-14-ol,

3β-[4-O-(β-D-dititoxosyl)-β-D-digitoxosyl]oxy-17β1(3 -fu ryl)-5β,14β-androstane-12β,14-diol,

3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3 -fu ryl)-5β,14β-androstane-14,16β-diol,

3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3 -fu ryl)-5β,14β-androstane-12β,14,16β-triol, and the lower alkanoates thereof.

These compounds can be prepared from the corresponding 3β-tridigitoxosyloxy-17β-(3-furyl)-5β,14β-androstane compounds disclosed in the U.S. Pat. No. 3,432,486 or 3β-bisdigitoxosyloxy-17β-(3-furyl)-5β,14β-androstane compounds of this invention by removing one or two digitoxosyl group according to the process of this invention or other methods e.g. Kaiser et al. cited above. They may also be prepared from the corresponding cardenolide bis- or mono-digitoxoside by reduction of butenolide ring to furan ring with action of reducing agent capable of converting butenelide to furyl group such as active aluminum hydride compounds e.g. dialkylaluminum hydrides, lithium dialkylaluminum hydride, etc.

The compounds of the present invention have valuable pharmacological activities. For example, they have strong digitaloid cardiotonic activity. They show inotropic effect, chronotropic effect, arrhythmia and finally contractile arrest of heart. They increase contractile amplitude of isolated guinea pig atria, isolated rabbit hearts and pigeon hearts, and show electro-cardiogram specific to digitaloid agents, bradycardia, retardation of heart rate, heart fibrillation when tested on pigeon. The Table I shows results of assay on cardiotonoic activity of two of the compounds. Furthermore, 3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3-f uryl)-5β,14β-androstane-12β, 14-diol, 3β-(β-D-digitoxosyl)-oxy-17β-(3-furyl)-5β,14β-and rostan-14-ol, 3β-(β-D-digitoxosyl)-oxy-17β-(3-furyl)-5β,14β-and rostane-12β,14-diol and 3β-(β-D-digitoxosyl)oxy-17β-(3-furyl)-5β,14β-andr ostane-14,16β-diol at concentration of 10 ^-6 , increased contractile amplitude of isolated guinea pig atria up to 140 - 200 %. Some of the compounds showed other pharmacological or physiological activities, for example, antiviral activity and cytotoxic activity in vitro, diuretic activity, respiration stimulating activity and anti-deoxycorticosterone activity.

TABLE I ______________________________________ isolated isolated rabbit disappear- guinea- heart ^b ) pigeon ance of compound pig 20 40 p.o. ^d ) i.p. ^e ) side atria ^a ) μg μg effects ^e ) ______________________________________ digitoxin 69 17 34 0.7 0.48 3 compound 44 10 19 -- -- 2 compound 66 6 17 11.2 3.96 2 II compound 48 14 21 5.4 2.23 1 III compound 76 16 24 6.7 2.18 1 IV ______________________________________ compound I: 3β-[4-O-(β-D-digitoxoyl-β-D-digitoxosyl)-β -D- digitoxosyl]oxy-17β-(3-furyl)-5β,14β- androstane-14-ol. compound II: 3β-[4-O-(β-D-digitoxosyl-β-D-digitoxosyl)-.bet a.-D- digitoxosyl]oxy-17β-(3-furyl)-5β ,14β- androstane-14,16β -diol. compound III: 3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy 17β-(3-furyl)-5β ,14β-androstane-14-ol. compound IV: 3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy- 17β-(3-furyl)-5β,14β-androstane-14,16β-diol. ^a ) The contractile amplitude of isolated guinea pig atria caused by the compound in a Ringer's solution at concentration of 10 ^-6 is recorded on kymograph and the results are represented by percent increase against initial value (Magnus method). ^b ) The compound in a Ringer's solution is passed through the coronar vessel of isolated rabbit heart in Ringer's solution. The movement of the heart is recorded on kymograph and maximum response is represented in percent increase against initial value (Langendorf method). ^c ) A method of Japanese Pharmacopoeia VII, United States Pharmacopoeia XVI, etc., for assay of digitalis preparations. A solution of the compound in ethanol is diluted with sufficient volume of isotonic sodium chloride solution and the resulted solution is injected repeatedly into alar vein of pigeon through cannula at a dose of 1 ml/kg for each injections, until the pigeon dies of cardiac arrest. The results are represented by mg per kg body weight. ^d ) The compound is mixed with gum arabicum and powdered finely. The mixture is mixed with water to make uniform suspension being 5 % gum arabicum suspension. The suspension is administered orally to pigeons and median lethal dosis (LD ₅₀ ) is calculated. The results are represente by mg per kg body weight. ^e ) Time in day required for disappearance of external symptoms of side effects of the compounds when tested on pigeon.?

From these data, it is concluded that the compounds of the present invention have cardiotonic activity as active as or stronger than digitoxin and corresponding butenolide derivatives. They are stronger than the corresponding tridigitoxosides. Their lethal dosis are higher than the butenolide compounds. In other words, their side effects are weaker than corresponding butenolide compounds. The main effects progress more rapidly than digitoxin but much slower than strospeside. The side effects disappeared more rapidly than the corresponding triglycosides or lactone compounds. Moreover, the appearance of the cardiotonic effect is mild and general appearances of animals administered with the compounds are mild and preferable. They can be administered orally or they can be absorbed through intestine. Digitoxin, the most practical but severe cardiotonic glycoside, tend to accumulate in the body of patient. Other compounds, e.g. gitoxin esters tend to show more individual difference of effects and side effects due to possible hydrolysis in the body. The compounds of the present invention overcome these insufficiency of the known compounds. As the compounds can be prepared in three steps process from abundant glycoside of digitalis plants, they are suitably produced in large amounts. Further they are more soluble in various pharmaceutically acceptable solvents than the corresponding lactone compounds or tridigitoxosides. These features show that the compounds of the present invention are strong, safe and mild cardiotonic agents which are easily preparable and suitable for clinical usage.

Afore mentioned activities show the compounds of the present invention is useful for its pharmacological activities. For example, they are utilized for treatment of heart diseases such as congestive heart caused from heart failure e.g. valvular affection, hypertension, arterioscleosis, myocardial infarction, etc; or edema, anasarca, seroperitoneum, hydrothorax, dyspnea and the like caused by heart failure or arrhythmia e.g. auricular fibrillation, absolute arrhythmia, extrasystoles, tachycardia, auricular flutter, or the like; or acute heart failure, acute congestive heart, acute heart hyposthenia, tonus disorder or the like, in a daily dosis of 0.1 μg to 10 mg per kilogram body weight for human and veterinary use. The content of the compounds in drugs are preferably uniform to make an unit dose tablet, pills, capsules or the like to use as maintenance dosis and/or saturation or digiralization. The preparations containing the compounds may also be used as diuretic agents for treatment of some symptoms caused by heart diseases and as respiration stimulating agents in some special cases.

These compounds may be utilized in a wide variety of oral or parenteral dosage forms, solely or in admixture with other co-acting compounds. They can be administered with a pharmaceutical carrier which can be a solid material or a liquid in which the compound is dissolved, dispersed or suspended. The solid compositions can take the form of tablets, powders, granules, capsules, pills or the like. The liquid composition may take the form of injections, suspensions, solutions, emulsions, syrups or elixirs. The tablets and granules may be coated.

The following examples are given by way of illustration only and are not intended as limitations of the present invention, many apparent variations of which are possible without departing from the spirit and scope thereof. The abbreviations have the conventional meanings.

EXAMPLE 1

A. To a stirred solution of 1 g of digitoxin in 80 ml of 95 % ethanol is added 1 g of sodium periodate in 10 ml of water. After 1 hour, the reaction mixture is filtrated to remove solid material and the filtrate is concentrated at temperature lower than 50°C. The concentrate is extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated under reduced pressure. The white powdery residue of dialdehyde shows single spot on thin-layer chromatogram and amounts 0.99 g. [α] _D ²³ + 8.4° (c = 0.478, methanol). Positive against Tollen reagent.

B-1. To a solution of 300 mg of the crude dialdehyde of (A) in 30 ml of methanol is added 4.5 ml of 0.05 N-hydrochloric acid and kept at room temperature for 24 hours. The reaction mixture is neutralized with 5 % aqueous solution of sodium hydrogen carbonate solution, evaporated to remove volatile solvent at under 50°C, and then extracted with chloroform. The chloroform extract is washed with water, dried over anhydrous sodium sulfate and evaporated to remove solvent. Purification of 225 mg of the crude product by thin-layer chromatography over silica gel utilizing a mixture of chloroform and acetone (2:1) as developing solvent and recrystallization from a mixture of ethyl acetate and n-hexane gives 124 mg of digitoxigenin-bisdigitoxoside, m.p. 228° - 230°C. Yield: 50 % from digitoxin. [α] _D ²³ + 7.3° (c = 0.833, methanol). UV: λ _max ^EtOH 217.5 nm. (ε 14,200). Anal. Calcd. for C ₃₅ H ₅₄ O ₁₀ : C, 66.22; H, 8.57. Found: C, 65.96; H, 8.53.

B-2. A solution of 200 mg of the crude dialdehyde of (A) in 20 ml of acetone containing 0.1 % of potassium hydrogen carbonate is kept at room temperature for 24 hours. The reaction mixture is neutralized with 5 % aqueous solution of acetic acid, concentrated under reduced pressure and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to remove the solvent. Purification of 166 mg of the residue by thin-layer chromatography over silica gel utilizing a mixture of chloroform and acetone (2:1) as developing solvent and recrystallization from a mixture of ethyl acetate and n-hexane affords 83 mg of digitoxigenin-bisdigitoxoside, m.p. 227° - 230°C. Yield: 50 % from digitoxin.

B-3. A solution of 200 mg of the crude dialdehyde of (A) in a mixture of 2 ml of chloroform and 6 ml of benzene is mixed with 8 g of neutral alumina and kept at room temperature for 20 hours. Then the mixture is filtrated to remove the solid material, and the solid material is washed 3 times with 100 ml of a mixture of methanol and chloroform (1:1). The filtrate solution and washed solvent are combined and evaporated to remove the solvent. Purification of 137 mg of the residue by thin-layer chromatography over silica gel utilizing a mixture of chloroform and acetone (2:1) and recrystallization from aqueous methanol affords 76 mg of digitoxigenin-bisdigitoxoside, m.p. 227° - 230°C. Yield: 45 % from digitoxin.

B-4. A stirred solution of 500 mg of the crude dialdehyde of (A) in 50 ml of 95 % methanol is mixed with 250 mg of sodium borohydride and kept at room temperature for 1 hour. The reaction mixture is neutralized with 5 % aqueous solution of acetic acid, evaporated under reduced pressure and then extracted with chloroform. The exact solution is washed with water, dried over anhydrous sodium sulfate and evaporated to remove the solvent. Purification of 503 mg of the residue by thin-layer chromatography gives crude dimethylol of single spot and negative to Tollen reagent. NMR data showed the structure. A solution of 450 mg of the crude dimethylol in 30 ml of methanol is mixed with 4.5 ml of 0.05 N hydrochloric acid and kept at room temperature for 3 hours. The reaction mixture is neutralized with 5 % aqueous solution of sodium hydrogen carbonate, evaporated under reduced pressure, and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated by dryness. Purification of the residue by recrystallization from a mixture of ethyl acetate and n-hexane gives 290 mg of digitoxigenin-bisdigitoxoside. Yield: more than 80 % from digitoxin.

B-5. A mixture of 200 mg of the crude dialdehyde of (A), 12 ml 95 % ethanol, 160 mg of phenylhydrazine hydrochloride, 240 mg of sodium acetate trihydrate and 4 ml of water is refluxed for 6 hours. The reaction mixture is concentrated under reduced pressure and extracted with chloroform. The extract solution is washed with 0.5 % hydrochloric acid and water, dried and evaporated to give 230 mg of residue, which gives 32 mg of digitoxigenin-bisdigitoxoside on recrystallization from a mixture of acetone and hexane, m.p. 227° - 230°C. Yield: 18.8 % from digitoxin.

EXAMPLE 2

To a stirred solution of 1 g of digoxin in a mixture of 20 ml of chloroform and 60 ml of methanol is added 10 ml of aqueous solution of 10 % sodium periodate dropwise and stirred for another 1.5 hours at room temperature. The reaction mixture is filtrated to remove solid material and the filtrate is diluted with 10 ml of water, evaporated under reduced pressure to remove volatile solvent, and then extracted with chloroform. The extract solution is washed with water and dried over anhydrous sodium sulfate and evaporated to leave 1.0 g of crude dialdehyde. The crude dialdehyde is dissolved in 120 ml of 95 % methanol and mixed with 500 mg of sodium borohydride with stirring at room temperature. The mixture containing dimethylol is stirred for another 30 minutes. The mixture is adjusted to pH 2.4 to thymol blue test paper with 0.1 N hydrochloric acid and kept at room temperature for 3 hours. The reaction mixture is neutralized with 5 % potassium carbonate solution to pH 6.8 - 7.0, evaporated to remove volatile solvent, and then is extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to remove the solvent. Purification of 707 mg of the residue by recrystallization from a mixture of chloroform and ether afforded 587 mg of pure crystals of digoxigenin-bisdigitoxoside, m.p. 195 - 197°C. Yield: 70.3 %. UV: λ _max ^EtOH 218 nm (ε 14,500). IR: ν _max ^{CHCL s} 3500, 1782, 1740, 1625 cm ^{- 1} . Anal. Calcd. for C ₃₅ H ₅₄ O ₁₁ : C, 64.59; H, 8.36. Found: C, 64.06; H, 8.46.

EXAMPLE 3

A. To a stirred solution of 1 g of gitoxin in 250 ml of a mixture of chloroform and methanol (1:1) is added a solution of 1 g of sodium periodate in 10 ml of water at room temperature, and the resulting mixed solution is kept at room temperature for 2 hours. The reaction mixture is filtrated to remove solid material, concentrated under reduced pressure to remove volatile solvent, and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to dryness. The residue amounted 980 mg which reduced Tollen reagent and showed single spot of dialdehyde on thin-layer chromatogram.

B-1. A solution of 200 mg of the crude dialdehyde of (A) in 20 ml of acetone containing 0.1 % of potassium hydrogen carbonate is kept at room temperature for 24 hours. The reaction mixture is neutralized with 5 % aqueous solution of acetic acid, concentrated under reduced pressure and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to dryness under reduced pressure. Purification of 148 mg of the residue by thin-layer chromatography over silica gel utilizing a mixture of chloroform and acetone (1:1) as developing solvent and recrystallization from a mixture of acetone and hexane affords 69 mg of pure crystals of gitoxigenin-bisdigitoxoside, m.p. 199° - 201°C. [α _D ²³ + 18.6° (c = 0.591, methanol). Yield: 40.5 % from gitoxin.

B-2. A solution of 200 mg of the crude dialdehyde of (A) in 20 ml of methanol is mixed with 3 ml of 0.05 N hydrochloric acid and kept at room temperature for 24 hours. The reaction mixture is neutralized with 5 % aqueous solution of sodium hydrogen carbonate, concentrated under reduced pressure and extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to dryness under reduced pressure. Purification of 139 mg of the residue by thin-layer chromatography over silica gel utilizing a mixture of chloroform and acetone (1:1) as developing solvent and recrystallization from a mixture of acetone and hexane affords 62 mg of gitoxigenin-bisdigitoxoside, m.p. 199°- 201°C. Yield: 36.4 % from gitoxin.

B-3. To a solution of 200 mg of the crude dialdehyde of (A) in 20 ml of methanol is added 25 mg of sodium borohydride and kept at room temperature for 1 hour. The reaction mixture is neutralized with 5 % aqueous solution of acetic acid, evaporated under reduced pressure, and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to dryness under reduced pressure. The residue did not reduce Tollen reagent and showed single spot of dimethylol on thin-layer chromatogram. A solution of 200 mg of the crude dimethylol in 20 ml of methanol is mixed with 3.0 ml of 0.05 N hydrochloric acid and kept at room temperature for 2 hours. The reaction mixture is neutralized with 5 % aqueous solution of sodium hydrogen carbonate, concentrated under reduced pressure, and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to remove the solvent. Purification of the residue by thin-layer chromatography over silica gel utilizing a mixture of chloroform and acetone (1:1) as developing solvent and recrystallization from a mixture of acetone and hexane affords 130 mg of gitoxigenin-bisdigitoxoside, m.p. 199° - 215°C. Yield: 78 percent from gitoxin. [α] _D ²³ + 18.6° (c = 0.591, methanol). UV: λ _max ^EtOH 219 nm. (ε 15,300). IR: ν _max ^CHCl .sbsp.3 3500, 1785, 1740, 1630, 1625 cm ^-1 . Anal. Calcd. for C ₃₅ H ₅₄ O ₁₁ : C, 64.59; H, 8.36. Found: C, 64.34; H, 8.47.

EXAMPLE 4

According to a process similar to that of Example 2, diginatin is oxidized with sodium periodate to afford dialdehyde, followed by reduction with sodium borohydride and hydrolysis with diluted hydrochloric acid giving diginatigenin-bis-digitoxoside.

EXAMPLE 5

To a solution of 140 mg of digitoxin-3'-acetate in 8 ml of 95% ethanol is added 140 mg of sodium periodate in 1.4 ml of water, and the mixture is kept at room temperature for 2 hours. The reaction mixture is filtrated to remove solid material, concentrated to remove volatile solvent, and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated under reduced pressure to dryness to leave 140 mg of white powdery dialdehyde which reduced Tollen reagent and showed characteristic signal at 0.30 τ in its n. m. r. spectrum. A solution of 140 mg of the crude dialdehyde in 20 ml of methanol is mixed with 3 ml of 0.05 N hydrochloric acid, and the mixture is kept at room temperature for 24 hours. The reaction mixture is neutralized with 5 % aqueous solution of sodium hydrogen carbonate, concentrated under reduced pressure and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to dryness under reduced pressure. Purification of the 108 mg of the residue by thin-layer chromatography over silica gel (a mixture of chloroform and acetone (2:1) as developing solvent) and recrystallization from a mixture of acetone and n-hexane affords 58 mg of digitoxigenin-bisdigitoxoside-3' -acetate, m.p. 140°- 145°C. Yield: 49.5 %. Anal. Calcd. for C ₃₇ H ₅₆ O ₁₁ H ₂ O: C, 63.96; H, 8.42. Found: C, 63.79; H, 8.76.

EXAMPLE 6

To a solution of 139 mg of digitoxin-3" -acetate in 8 ml of 95 % ethanol is added a solution of 139 mg of sodium periodate in 1.4 ml of water, and the mixture is kept at room temperature for 3 hours. The reaction mixture is filtrated to remove solid material, concentrated to remove volatile solvent, and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated under reduced pressure to leave 146 mg of white powdery crude dialdehyde which reduced Tollen reagent and showed characteristic signals at 0.22 τ and 0.44 τ in its n. m. r. spectrum. The crude dialdehyde is dissolved in 24 ml of methanol, mixed with 3.6 ml of 0.05 N hydrochloric acid and kept at room temperature for 24 hours. The reaction mixture is neutralized with 5 % aqueous solution of acetic acid, concentrated under reduced pressure, and extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to dryness. Purification of 116 mg of the residue by thin-layer chromatography over silica gel and recrystallization from aqueous methanol gives 62 mg of digitoxigenin-bis-digitoxoside-3"-acetate, m.p. 143° - 147°C. Yield: 55.5 %. [α] _D ²³ + 17.5° (c = 0.258, methanol). Anal. Calcd. for C ₃₇ H ₅₆ O ₁₁ 1/2 H ₂ O: C, 64.80; H, 8.38; CH ₃ CO, 6.28. Found: C, 64.74; H, 8.25; CH ₃ CO, 6.01.

EXAMPLE 7

To a solution of 150 mg of digitoxigenin-bis-digitoxoside in 10 ml of 95 % ethanol is added a solution of 150 mg of sodium periodate in 2 ml of water, and the mixture is kept at room temperature for 1 hour. The reaction mixture is filtrated to remove the solid material, concentrated to remove volatile solvent and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to dryness. The residue showed single spot of dialdehyde on thin-layer chromatogram and reduced Tollen reagent. The dialdehyde (150 mg) dissolved in 15 ml of 95 % methanol is mixed with 75 mg of sodium borohydride, and kept at room temperature for 2 hours. The reaction mixture is neutralized with 5 % aqueous solution of acetic acid, concentrated under reduced pressure and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to dryness. The residue showed single spot of dimethylol on thin-layer chromatogram and did not reduce Tollen reagent. The crude dimethylol (135 mg) dissolved in 12 ml of methanol is mixed with 1.8 ml of 0.05 N hydrochloric acid and kept at room temperature for 2 hours. The reaction mixture is neutralized with 5 % aqueous solution of sodium hydrogen carbonate, evaporated to remove volatile solvent, and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to dryness. Purification of 118 mg of the residue by recrystallization from a mixture of ethyl acetate and n-hexane gives digitoxigenin-monodigitoxoside, m.p. 197° - 200°C. UV: λ _max ^EtOH 218 nm (ε 15,090). [α] _D ²³ - 5.2° (c = 0.327, methanol). Yield: 76 percent.

EXAMPLE 8

To a solution of 50 mg of digoxigenin-bisdigitoxoside in 3 ml of 95 % ethanol is added a solution of 50 mg of sodium periodate in 0.5 ml of water, and the mixture is kept at room temperature for 1 hour. The reaction mixture is filtrated to remove the solid material, concentrated to remove volatile solvent and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to dryness. The residue showed single spot of dialdehyde on thin-layer chromatogram and reduced Tollen reagent. The crude dialdehyde (52 mg) dissolved in 3 ml of 95 % methanol is mixed with 10 mg of sodium borohydride, and kept at room temperature for 1 hour. The reaction mixture is neutralized with 5 % aqueous solution of acetic acid, concentrated under reduced pressure and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to dryness. The residue showed single spot of dimethylol on thin-layer chromatogram and did not reduce Tollen reagent. The crude dimethylol (45 mg) dissolved in 2 ml of methanol is mixed with 0.5 ml of 0.05 N hydrochloric acid and kept at room temperature for 1 hour. The reaction mixture is neutralized with 5 % aqueous solution of sodium hydrogen carbonate, evaporated to remove volatile solvent and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to dryness. Purification of 44 mg of the residue by recrystallization from a mixture of ethyl acetate and n-hexane gives digoxigenin-monodigitoxoside, m.p. 210° - 212°C.

EXAMPLE 9

To a solution of 250 mg of gitoxigenin-bisdigitoxoside in 20 ml of 95 % ethanol is added a solution of 250 mg of sodium periodate in 2.5 ml of water, and the mixture is kept at room temperature for 1.5 hour. The reaction mixture is filtrated to remove the solid material, concentrated to remove volatile solvent and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to dryness. The residue showed single spot of dialdehyde on thin-layer chromatogram and reduced Tollen reagent. The crude dialdehyde (250 mg) dissolved in 20 ml of 95 % methanol is mixed with 125 mg of sodium borohydride, and kept at room temperature for 2 hours. The reaction mixture is neutralized with 5 % aqueous solution of acetic acid, concentrated under reduced pressure and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to dryness. The residue showed single spot of dimethylol on thin-layer chromatogram and did not reduce Tollen reagent. The crude dimethylol (230 mg) dissolved in 20 ml of methanol is mixed with 3.5 ml of 0.05 N hydrochloric acid and kept at room temperature for 2 hours. The reaction mixture is neutralized with 5 % aqueous solution of sodium hydrogen carbonate, evaporated to remove volatile solvent and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to dryness. Purification of 207 mg of the residue by recrystallization from a mixture of ethyl acetate and n-hexane gives gitoxigenin-monodigitoxoside, m.p. 216° - 218°C.

EXAMPLE 10

To a solution of 100 mg of 3β-(β-D-digitoxosyl-β-D-digitoxosyl-β-D-digitoxosyl)ox y-17β-(3-furyl)-5β,14β-androstan-14-ol in 12 ml of 95 % ethanol is added 100 mg of sodium periodate in 1 ml of water, and the mixture is kept at room temperature for 1 hour. The reaction mixture is concentrated under reduced pressure and extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to dryness under reduced pressure. The residue reduced Tollen reagent and showed single spot of dialdehyde on its thin-layer chromatogram. A solution of 98 mg of the crude dialdehyde in 10 ml of 95 % methanol is added 50 mg of sodium borohydride, and the mixture is kept at room temperature under nitrogen atmosphere for 1 hour. The reaction mixture is neutralized with 5 % aqueous solution of acetic acid, concentrated at room temperature under reduced pressure, and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated under reduced pressure to dryness. The residue did not reduce Tollen reagent and showed single spot of dimethylol on its thin-layer chromatogram. A solution of 100 mg of the crude dimethylol in 5 ml of methanol is mixed with 0.75 ml of 0.05 N hydrochloric acid and the mixture is kept at room temperature for 3 hours. The reaction mixture is neutralized with 5 % aqueous solution of sodium hydrogen carbonate, and extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated under reduced pressure to dryness. Purification of 70 mg of the residue by recrystallization from a mixture of acetone and n-hexane affords 59 mg of pure 3β-[4-O-(β -D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3-furyl)-5β,14.b et a.-androstan-14-ol, m.p. 199 - 200°C. Yield: 74.3 %. [α] _D ²³ + 1.0 ± 0.8° (c = 0.516, methanol). UV: λ _max ^EtOH 212 nm (ε 5,280). IR: ν _max ^CHCl .sbsp.3 3,500 - 3600 cm ^-1 . Anal. Calcd. for C ₃₅ H ₅₄ O ₉ : C, 67.93; H, 8.80. Found: C, 67.96; H, 8.97.

EXAMPLE 11

To a stirred solution of 50 mg of 3β-(β-D-digitoxosyl-β-D-digitoxosyl-βD-digitoxosyl)oxy -17β-(3-furyl)-5β,14β-androstane-12β,14-diol in 6 ml of ethanol is added dropwise a solution of 50 mg of sodium periodate in 0.5 ml of water at room temperature. After stirring for another 30 minutes, the reaction mixture is filtrated to remove solid material, diluted with 20 ml of water, evaporated under reduced pressure to remove volatile solvent, and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated under reduced pressure to dryness to obtain 44 mg of crude dialdehyde. A solution of 43 mg of the crude dialdehyde in 3 ml of 95 % methanol is mixed with 20 mg of sodium borohydride and the mixture is kept at room temperature for 1 hour. The reaction mixture containing crude dimethylol is acidified with 0.1 N hydrochloric acid to pH 2.8 to thymol blue test paper. After stirring for 4 hours under nitrogen atmosphere, the solution is neutralized with 5 % sodium hydrogen carbonate, concentrated and extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to dryness. Purification of 41 mg of the crude product by thin-layer chromatography over silica gel utilizing a mixture of chloroform and acetone (2:1) as developing solvent and recrystallization from a mixture of chloroform and ether gives 30 mg of crystals of 3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3-f uryl)-5β,14β-androstane-12β,14-diol, m.p. 136 - 139°C. [α] _D ²² + 0.8 ± 0.4°; [α] ₃₆₅ ²² + 6.3 ± 0.5° (c = 1.016, chloroform). UV: λ _max ^EtOH 212 n, (ε 4,640). IR: ν _max ^CHCl .sbsp.3 3500, 1600 cm ^-1 . Anal. Calcd. for C ₃₅ H ₅₄ O ₁₀ 1/2 H ₂ O: C, 65.30; H, 8.61. Found: C, 65.76; H, 9.13.

EXAMPLE 12

To a stirred solution of 800 mg of 3β-(β-D-digitoxosyl-β-D-digitoxosyl-β-D-digitoxosyl)ox y-17β-(3-furyl)-5β,14β-androstane-14,16β-diol in 60 ml of ethanol is added dropwise a solution of 800 mg of sodium periodate in 8 ml of water at room temperature. After stirring for another 45 minutes, the reaction mixture is filtrated to remove solid material, diluted with 20 ml of water, evaporated under reduced pressure to remove volatile solvent, and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated under reduced pressure to dryness to obtain 909 mg of crude dialdehyde. A solution of 900 mg of the crude dialdehyde in 80 ml of 95 % methanol is mixed with 80 mg of sodium borohydride and the mixture is kept at room temperature for 1 hour. The reaction mixture containing crude dimethylol is acidified with 0.1 N hydrochloric acid to pH 2.8 to thymol blue test paper. After stirring for 4 hours under nitrogen atmosphere, the solution is neutralized with 5 % sodium hydrogen carbonate, concentrated and extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to dryness. Purification of 724 mg of the crude product by thin-layer chromatography over silica gel utilizing a mixture of chloroform and acetone (2:1) as developing solvent and recrystallization from a mixture of acetone and hexane gives crystals of 3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3-f uryl)-5β,14β-androstane-14,16β-diol, m.p. 105 - 135°C. [α] _D ²⁷ + 10.4 ± 0.9° (c = 0.539, methanol). UV: λ _max ^EtOH 212 nm (ε 5,080). IR: ν _max ^CHCl .sbsp.3 3,500, 1603 cm ^-1 . Anal. Calcd. for C ₃₅ H ₅₄ O ₁₀ 3/2 H ₂ O: C, 63.58; H, 8.68. Found: C, 63.59; H, 8.71.

EXAMPLE 13

To a solution of 100 mg of 3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3-f uryl)-5β,14β-androstan-14-ol in 10 ml of 95 % ethanol is added 1.0 ml of 10 % aqueous solution of sodium periodate and the mixture is stirred for 1 hour at room temperature. The reaction mixture is diluted with water, evaporated to remove methanol, and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to remove the solvent to leave 103 mg of crude dialdehyde. The crude dialdehyde is dissolved in 8 ml of 95 % methanol, mixed with 15 mg of sodium borohydride, and stirred for 0.5 hour at room temperature. The reaction mixture containing dimethylol is acidified with 0.1 N hydrochloric acid to pH 2.4 and kept at room temperature for 3 hours. Then the mixture is neutralized with 5 % aqueous solution of sodium hydrogen carbonate to pH 7.0, diluted with water, evaporated to remove volatile solvent and extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to remove the solvent. Purification of 95 mg of the crude product by recrystallization from a mixture of methanol and ether gives 77 mg of the pure crystals of 3β-(β-D-digitoxosyl)oxy-17β-(3-furyl)-5β,14β-andr ostan-14-ol, m.p. 95 - 97°C. [α] _D ²² - 10.8 ± 1.4° (c = 0.361, methanol). UV: λ _max ^EtOH 212 nm (ε 5,430). IR: ν _max ^CHCl .sbsp.3 3400 - 3600, 1600 cm ^-1 . Anal. Calcd. for C ₂₉ H ₄₄ O ₆ 1/2 H ₂ O: C, 69.99; H, 9.11. Found: C. 70.30; H, 9.43.

EXAMPLE 14

To a solution of 144 mg of 3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3-f uryl)-5β,14β-androstane-14,16β-diol in 12 ml of 95 % aqueous methanol is added 1.4 ml of 10 % aqueous solution of sodium periodate and the mixture is stirred for 1 hour at room temperature. The reaction mixture is diluted with water, evaporated to remove methanol, and then extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to remove the solvent, to leave 140 mg of crude dialdehyde. The crude dialdehyde is dissolved in 12 ml of 95 % methanol, mixed with 20 mg of sodium borohydride, and stirred for 1.5 hours at room temperature. The reaction mixture containing dimethylol is acidified with 0.1 N hydrochloric acid to pH 2.6 and kept at room temperature for 4 hours. Then the mixture is neutralized with 5 % aqueous solution of sodium hydrogen carbonate to pH 7.0, diluted with water, evaporated to remove volatile solvent and extracted with chloroform. The extract solution is washed twice with water, dried over anhydrous sodium sulfate and evaporated to remove the solvent. Purification of 106 mg of the crude product by recrystallization from a mixture of methanol and ether affords 70 mg of the pure crystals of 3β-(β-D-digitoxosyl)oxy-17β-(3-furyl)-5β,14β-andr ostane-14,16β-diol, m.p. 218-219°C. [α] _D ²² ± 0°; [α] ₃₆₅ ²² + 11.2 ± 2.0° (c = 0.403, methanol). UV: λ _max ^EtOH 212 nm (ε 5,600). IR: ν _max ^Nujol 3450 cm ^-1 . Anal. Calcd. for C ₂₉ H ₄₄ O ₇ : C, 69.02; H, 8.79. Found: C, 69.07; H, 8.94.

EXAMPLE 15

To a solution of 120 mg of digitoxigenin-mono-digitoxoside in 2 ml of dry tetrahydrofuran cooled at from -20°C to -25°C under nitrogen atmosphere is added dropwise 1.20 ml of a solution of di-isobutylaluminum hydride in tetrahydrofuran (208 mg/ml). After 45 minutes, the reaction mixture is mixed with 3 ml of 2 N-sulfuric acid and stirred for 15 minutes at 0°C, and then is extracted with chloroform. The extract solution is washed with 5 % aqueous solution of sodium hydrogen carbonate and water, dried over sodium sulfate and evaporated to remove the solvent. Purification of 118 mg of the residue by preparative thin-layer chromatography over silica gel utilizing a mixture of acetone and chloroform (1:2) as developing solvent and recrystallization from a mixture of ether and pentane affords 65 mg of 3β-(β-D-digitoxosyl)oxy-17β-(3-furyl)-5β,14β-andr ostan-14-ol, m.p. 95° - 97°C. [α] _D ²² - 10.8 ± 1.4° (c = 0.361, methanol). UV: λ _max ^EtOH 212 nm (ε 5,430). IR: ν _max ^CHCl .sbsp.3 3400 - 3500, 1600 cm ^-1 .

EXAMPLE 16

To a solution of 450 mg of digoxigenin-bis-digitoxoside in 10 ml of dry tetrahydrofuran cooled at -30°C is added 8.8 ml of a solution of di-isobutylaluminum hydride in tetrahydrofuran (258 mg/ml) in three portions under nitrogen atmosphere. After 45 minutes, the reaction mixture is mixed with 15 ml of 2 N sulfuric acid and stirred at 0°C for 15 minutes, and then extracted with chloroform. The extract solution is washed with 5 % aqueous solution of sodium hydrogen carbonate and water, dried over anhydrous sodium sulfate and evaporated to remove the solvent. Purification of 390 mg of the crude product by thin-layer chromatography over silica gel utilizing a mixture of chloroform and acetone (2:1) as developing solvent and recrystallization from a mixture of chloroform and ether gives 303 mg of 3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3-f uryl)-5β,14β-androstane-12β,14-diol, m.p. 136° - 139°C, [α] _D ²² + 0.8 ± 0.4° (c = 1.016, chloroform). UV: λ _max ^EtOH 212 nm (ε 4,640). IR: ν _max ^CHCl .sbsp.3 3500 cm ^-1 .

EXAMPLE 17

To a stirred solution of 300 mg of gitoxigenin-bisdigitoxoside in 5 ml of tetrahydrofuran is added 1.58 ml of di-isobutylaluminum hydride in dry tetrahydrofuran (1.1 mole equivalent) at -25°C under nitrogen atmosphere. After 30 minutes, 5 ml of 2 N sulfuric acid is added into the reaction mixture, and the mixture is stirred under ice-cooling for 10 minutes, and then the resultant solution is extracted with chloroform. The extract solution is washed with an aqueous solution of potassium carbonate and water, dried over anhydrous sodium sulfate and evaporated under reduced pressure. Purification of the crude product by crystallization from a mixture of ether and pentane gives 108 mg of 3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3-f uryl)-5β,14β-androstane-14,16β-diol, m.p. 105° - 135°C. [α] _D ²⁷ + 10.4 ± 0.9° (c = 0.539, methanol).

EXAMPLE 18

To a solution of 400 mg of digitoxin in 20 ml of dioxane is added 500 mg of lead tetraacetate, and the mixture is stirred at room temperature for 1.5 hours. The reaction mixture is filtrated to remove solid material and the filtrate is diluted with 10 ml of water. The diluted filtrate is evaporated to remove volatile solvent and extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to remove the solvent. Purification of 358 mg of the residue by thin-layer chromatography over silica gel using a mixture of chloroform and ethyl acetate (1:1) as developing solvent and recrystallization from a mixture of ether and petroleum ether gives the dialdehyde identical with that obtained in Example 1 (A). The dialdehyde obtained above is dissolved in 95 % ethanol and mixed with 10 mg of sodium borohydride. After 1, hour, the mixture is acidified to pH 2.4 to thymol blue test paper with 1 N sulfuric acid and kept at room temperature for 30 minutes. The reaction mixture is neutralized with 0.1 N sodium carbonate solution, evaporated to remove volatile solvent and extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to dryness. Purification of the residue by thin-layer chromatography over silica gel using a mixture of chloroform and acetone (2:1) as developing solvent and recrystallization from a mixture of acetone and n-hexane gives 287 mg of digitoxigenin-bisdigitoxoside, m.p. 226° - 230°C. Yield: 87 %.

EXAMPLE 19

To a solution of 100 mg of digitoxin in 4 ml of chloroform and 4 ml of carbon tetrachloride cooled at 0°C is added 100 mg of powdered ruthenium tetroxide. After 30 minutes stirring, the mixture is mixed with a small amount of methanol, and filtrated to remove solid material. The filtrate is evaporated to dryness to leave 99 mg of the residue identical with dialdehyde obtained by the process of Example 1 (A). The dialdehyde is dissolved in 1 ml of 95 % ethanol, mixed with 8 mg of sodium borohydride and the mixture is kept at room temperature for 0.5 hour. The reaction mixture containing crude dimethylol is acidified to pH 3.5 to thymol blue test paper with 0.1 N sulfuric acid. After 3 hours, the reaction mixture is neutralized with 5 % sodium hydrogen carbonate, concentrated and extracted with chloroform. The extract solution is washed with water, dried over anhydrous sodium sulfate and evaporated to dryness. Purification of the residue by thin-layer chromatography and recrystallization gives 73 mg of digitoxigenin-bisdigitoxoside, m.p. 228° - 230°C. Yield: 89 %.

EXAMPLE 20

To a solution of 100 mg of digitoxin in 5 ml of acetic acid is added 1 ml of water and 500 mg of powdered sodium oismuthate. After shaking for 3 hours at room temperature, the mixture is filtered to remove the solid material. The solid material is washed thoroughly with ethyl acetate. Mixture of the filtrate and washed solvent is evaporated to dryness. The residue is treated with sodium borohydride and diluted sulfuric acid according to the process of Example 1 (B-4) to afford 70 mg of digitoxigenin-bisdigitoxoside, m.p. 228° - 230°C. Yield: 85 %.

EXAMPLE 21

To a solution of 10 mg of digitoxin in 1 ml of benzene is added 13 mg of iodosobenzene diacetate. After stirring for 5 hours, the reaction mixture is washed with aqueous solution of sodium bisulfate and water, dried over anhydrous sodium sulfate and evaporated to dryness. The residue showed spot of dialdehyde on its thin-layer chromatogram. The residue is treated with sodium borohydride and diluted sulfuric acid according to the process of Example 1 (B-4) to afford digitoxigenin-bisdigitoxoside, m.p. 228° - 231°C.

EXAMPLE 22

A mixture of 9 mg of 3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3-f uryl)-5β, 14β-androstane-14,16β-diol, 0.5 ml of pyridine and 0.5 ml of acetic anhydride is kept at room temperature for 5 days. The reaction mixture is poured onto iced water and extracted with chloroform. The extract solution is washed successively with water, aqueous sodium carbonate solution and diluted hydrochloric acid and water, dried over anhydrous sodium sulfate and evaporated to dryness. Purification of 12 mg of the residue by thin-layer chromatography over silica gel using a mixture of ethyl acetate and benzene (1:2) as developing solvent and recrystallization from a mixture of ether and n-hexane gives 3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3-f uryl)-5β,14β-androstane-14,16β-diol tetraacetate, m.p. 103° - 106°C (amorphous).

EXAMPLE 23

A tablet is prepared in conventional manner from 0.2 mg of 3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3-f uryl)-5β,14β-androstane-14,16β-diol, 50 mg of starch and a small amount of magnesium stearate. Six tablets per day for saturation or two tablets per day for maintenance dosis are given to a patient.

EXAMPLE 24

A colored powder consisting of 1 weight of 3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3-f uryl)-5β,14β-androstane-14,16β-diol and 10,000 weights of starch.

EXAMPLE 25

An injection, containing a solution of 2 mg of 3β-[4-O-(β-D-digitoxosyl)-β-D-digitoxosyl]oxy-17β-(3-f uryl)-5β,14β-androstan-14-ol in 1 ml of 20 % alcohol and stabilizer sealed under nitrogen gas, is administered to a patient at a dosis of 2 to 4 ml per a day for quick saturation or critical cases.