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US4060606A Expired / Lapsed US ⏱️ 0.0 years remaining

16-Ethers of fusidic acid derivatives

Assignee: Leo Pharma AS
•
Filing: 1976-06-08
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Granted: 1977-11-29
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Expires: 1996-06-08
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Abstract

Abstract The present invention relates to a new series of fusidic acid derivatives, to salts and easily hydrolysable esters thereof, to the preparation of these compounds, and to pharmaceutical compositions containing the compounds. The new compounds have the general formula ##STR1## in which the C 24-25 bond is a single or a double bond, and in which Q 1 and Q 2 stand for ##STR2## or oxygen; A stands for oxygen, sulphur or a sulfinyl radical; R 1 stands for a straight or branched alkyl radical having from 1 to 8 carbon atoms, an alkenyl or alkynyl radical having from 2 to 6 carbon atoms, a cycloalkyl radical having from 3 to 7 carbon atoms in the alicyclic ring, an aryl or aralkyl radical, a heterocyclic radical having 5 or 6 ring atoms, and containing oxygen, sulphur or nitrogen atoms, and pharmaceutically acceptable salts and easily hydrolysable esters thereof. The compound of the present invention show interesting antimicrobial and pharmacokinetic properties. Thereby the compounds of the invention can be used in the treatment of bacterial infections in humans and animals.

Inventors

  • 👤 Welf von Daehne
  • 👤 Poul Rodbroe Rasmussen

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 22:01
CPC Classifications
C; C07; C07J; C07J31/00; C07J31/003; C07J13/00; C07J13/007; C07J41/00; C07J41/0033; C07J41/0055; C07J43/00; C07J43/003

Claims Analysis

Total Claims: 62
Claim 1
Independent Claim 157 words
A compound of the following formula I: ##STR34## in which the C 24-25 bond is a single or a double bond, and in which Q 1 and Q 2 stand for ##STR35## or oxygen; A stands for oxygen, sulphur or a sulfinyl radical; R 1 stands for a straight or branched alkyl radical having from 1 to 8 carbon atoms, an alkenyl or alkynyl radical having from 2 to 6 carbon atoms, a cycloalkyl radical having from 3 to 7 carbon atoms in the alkyclic ring, an aryl, aralkyl or heterocyclylalkyl radical, or a heterocyclic radical having 5 or 6 ring atoms and containing oxygen, sulphur or nitrogen selected from the group consisting of 2- or 3-pyrrolyl, 2- or 3-furyl, 2- or 3-thienyl, 2-, 3- or 4-pyridyl, 2-, 4- or 5-pyrimidinyl, 2- or 3-pyrazolyl, imidazolyl, triazolyl, tetrazolyl, thiazolyl and thiadiazolyl, all R 1 radicals being optionally substituted; and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 2
Dependent Claim 157 words
A compound of the following formula I: ##STR34## in which the C 24-25 bond is a single or a double bond, and in which Q 1 and Q 2 stand for ##STR35## or oxygen; A stands for oxygen, sulphur or a sulfinyl radical; R 1 stands for a straight or branched alkyl radical having from 1 to 8 carbon atoms, an alkenyl or alkynyl radical having from 2 to 6 carbon atoms, a cycloalkyl radical having from 3 to 7 carbon atoms in the alkyclic ring, an aryl, aralkyl or heterocyclylalkyl radical, or a heterocyclic radical having 5 or 6 ring atoms and containing oxygen, sulphur or nitrogen selected from the group consisting of 2- or 3-pyrrolyl, 2- or 3-furyl, 2- or 3-thienyl, 2-, 3- or 4-pyridyl, 2-, 4- or 5-pyrimidinyl, 2- or 3-pyrazolyl, imidazolyl, triazolyl, tetrazolyl, thiazolyl and thiadiazolyl, all R 1 radicals being optionally substituted; and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 3
Dependent Claim 69 words
A compound of formula I, in which the C 24-25 bond is a single or a double bond, Q 1 and Q 2 both stand for ##STR36## A stands for oxygen; R 1 stands for a straight or branched alkyl radical having from 1 to 4 carbon atoms and being optionally substituted with halogen atoms, hydroxy or azido groups, and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 4
Dependent Claim 69 words
A compound of formula I, in which the C 24-25 bond is a single or a double bond, Q 1 and Q 2 both stand for ##STR36## A stands for oxygen; R 1 stands for a straight or branched alkyl radical having from 1 to 4 carbon atoms and being optionally substituted with halogen atoms, hydroxy or azido groups, and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 5
Dependent Claim 69 words
A compound of formula I, in which the C 24-25 bond is a single or a double bond, Q 1 and Q 2 both stand for ##STR37## A stands for sulphur; R 1 stands for a straight or branched alkyl radical having from 1 to 4 carbon atoms and being optionally substituted with halogen atoms, hydroxy or azido groups, and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 6
Dependent Claim 69 words
A compound of formula I, in which the C 24-25 bond is a single or a double bond, Q 1 and Q 2 both stand for ##STR37## A stands for sulphur; R 1 stands for a straight or branched alkyl radical having from 1 to 4 carbon atoms and being optionally substituted with halogen atoms, hydroxy or azido groups, and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 7
Dependent Claim 72 words
A compound of formula I, in which the C 24-25 bond is a single or a double bond, Q 1 and Q 2 both stand for ##STR38## A stands for a sulfinyl radical; R 1 stands for a straight or branched alkyl radical having from 1 to 4 carbon atoms and being optionally substituted with halogen atoms, hydroxy or azido groups, and pharmaceutically acceptable salts and non toxic easily hydrolyzable esters thereof.
Claim 8
Dependent Claim 72 words
A compound of formula I, in which the C 24-25 bond is a single or a double bond, Q 1 and Q 2 both stand for ##STR38## A stands for a sulfinyl radical; R 1 stands for a straight or branched alkyl radical having from 1 to 4 carbon atoms and being optionally substituted with halogen atoms, hydroxy or azido groups, and pharmaceutically acceptable salts and non toxic easily hydrolyzable esters thereof.
Claim 9
Dependent Claim 74 words
A compound of formula I, in which the C 24-25 bond is a single or a double bond, one of Q 1 and Q 2 is oxygen and the other is ##STR39## A stands for oxygen; R 1 stands for a straight or branched alkyl radical having from 1 to 4 carbon atoms and being optionally substituted with halogen atoms, hydroxy or azido groups, and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 10
Dependent Claim 74 words
A compound of formula I, in which the C 24-25 bond is a single or a double bond, one of Q 1 and Q 2 is oxygen and the other is ##STR39## A stands for oxygen; R 1 stands for a straight or branched alkyl radical having from 1 to 4 carbon atoms and being optionally substituted with halogen atoms, hydroxy or azido groups, and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 11
Dependent Claim 74 words
A compound of formula I, in which the C 24-25 bond is a single or a double bond, one of Q 1 and Q 2 is oxygen and the other is ##STR40## A stands for sulphur; R 1 stands for a straight or branched alkyl radical having from 1 to 4 carbon atoms and being optionally substituted with halogen atoms, hydroxy or azido groups, and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 12
Dependent Claim 74 words
A compound of formula I, in which the C 24-25 bond is a single or a double bond, one of Q 1 and Q 2 is oxygen and the other is ##STR40## A stands for sulphur; R 1 stands for a straight or branched alkyl radical having from 1 to 4 carbon atoms and being optionally substituted with halogen atoms, hydroxy or azido groups, and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 13
Dependent Claim 74 words
A compound of formula I, in which the C 24-25 bond is a single or a double bond, one of Q 1 and Q 2 is oxygen and the other is ##STR41## A stands for sulfinyl; R 1 stands for a straight or branched alkyl radical having from 1 to 4 carbon atoms and being optionally substituted with halogen atoms, hydroxy or azido groups, and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 14
Dependent Claim 74 words
A compound of formula I, in which the C 24-25 bond is a single or a double bond, one of Q 1 and Q 2 is oxygen and the other is ##STR41## A stands for sulfinyl; R 1 stands for a straight or branched alkyl radical having from 1 to 4 carbon atoms and being optionally substituted with halogen atoms, hydroxy or azido groups, and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 15
Dependent Claim 18 words
16-Deacetoxy-16β-isopropylthiofusidic acid and its C 24-25 -dihydro analogue and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 16
Dependent Claim 18 words
16-Deacetoxy-16β-isopropylthiofusidic acid and its C 24-25 -dihydro analogue and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 17
Dependent Claim 18 words
16-Deacetoxy-16β-isopropylsulfinylfusidic acid and its C 24-25 -dihydro analogue, and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 18
Dependent Claim 18 words
16-Deacetoxy-16β-isopropylsulfinylfusidic acid and its C 24-25 -dihydro analogue, and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 19
Dependent Claim 18 words
11-Keto-16-deacetoxy-16β-isopropylthiofusidic acid, and its C 24-25 -dihydro analogue, and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 20
Dependent Claim 18 words
11-Keto-16-deacetoxy-16β-isopropylthiofusidic acid, and its C 24-25 -dihydro analogue, and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 21
Dependent Claim 18 words
3-Keto-16-deacetoxy-16β-isopropylthiofusidic acid, and its C 24-25 -dihydro analogue and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 22
Dependent Claim 18 words
3-Keto-16-deacetoxy-16β-isopropylthiofusidic acid, and its C 24-25 -dihydro analogue and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 23
Dependent Claim 16 words
16-Deacetoxy-16β-ethoxyfusidic acid and its 11-keto analogue, and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 24
Dependent Claim 16 words
16-Deacetoxy-16β-ethoxyfusidic acid and its 11-keto analogue, and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 25
Dependent Claim 17 words
16-Deacetoxy-16β-(2'-fluoroethoxy)fusidic acid and its 11-keto analogue, and non toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 26
Dependent Claim 17 words
16-Deacetoxy-16β-(2'-fluoroethoxy)fusidic acid and its 11-keto analogue, and non toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 27
Dependent Claim 16 words
16-Deacetoxy-16β-(2',2',2'-trifluoroethoxy)fusidic acid and its 11-keto analogue, and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 28
Dependent Claim 16 words
16-Deacetoxy-16β-(2',2',2'-trifluoroethoxy)fusidic acid and its 11-keto analogue, and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 29
Dependent Claim 13 words
16-Deacetoxy-16β-(1',3'-difluoroisopropyloxy) fusidic acid and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 30
Dependent Claim 13 words
16-Deacetoxy-16β-(1',3'-difluoroisopropyloxy) fusidic acid and non-toxic pharmaceutically acceptable salts and easily hydrolyzable esters thereof.
Claim 31
Independent Claim 312 words
A method for the preparation of a compound of formula I ##STR42## in which the C 24-25 bond is a single or a double bond, and in which Q 1 and Q 2 stand for ##STR43## or oxygen; A stands for oxygen, sulphur or a sulfinyl radical; R 1 stands for a straight or branched alkyl radical having from 1 to 8 carbon atoms, an alkenyl or alkynyl radical having from 2 to 6 carbon atoms, a cycloalkyl radical having from 3 to 7 carbon atoms in the alicyclic ring, an aryl, aralkyl or heterocyclylalkyl radical, or a heterocyclic radical having 5 or 6 ring atoms and containing oxygen, sulphur or nitrogen atoms, all R 1 radicals being optionally substituted; and pharmaceutically acceptable salts and easily hydrolyzable esters thereof comprising reacting a compound of formula Vb ##STR44## in which Q 1 ' is Q 1 or ##STR45## R 2 being an alkanoyl, an aralkanoyl or an aroyl radical; Q 2 is as defined above; Y stands for chlorine, bromine or iodine; and R 3 stands for a straight or branched alkyl radical having from 1 to 6 carbon atoms, an aralkyl radical an alkanoyl- or aroylmethyl radical, an alkanoyl- or aroyl-oxyalkyl radical, an alkyloxymethyl or a cyanomethyl radical; with a compound of formula VII: R 1 -A-H, in which R 1 is as defined above and A represents oxygen or sulphur, yielding a compound of formula VIII: ##STR46## in which Q 1 ', Q 2 , R 1 and R 3 are as defined above, and A is oxygen or sulphur, which compound is thereafter subjected to a hydrolysis, if desired, and a compound of formula I, A being sulphur, optionally is oxidized to a compound of formula I, A being a sulfinyl radical; and the free acid can be transformed into a pharmaceutically acceptable salt or an easily hydrolyzable ester thereof.
Claim 32
Independent Claim 312 words
A method for the preparation of a compound of formula I ##STR42## in which the C 24-25 bond is a single or a double bond, and in which Q 1 and Q 2 stand for ##STR43## or oxygen; A stands for oxygen, sulphur or a sulfinyl radical; R 1 stands for a straight or branched alkyl radical having from 1 to 8 carbon atoms, an alkenyl or alkynyl radical having from 2 to 6 carbon atoms, a cycloalkyl radical having from 3 to 7 carbon atoms in the alicyclic ring, an aryl, aralkyl or heterocyclylalkyl radical, or a heterocyclic radical having 5 or 6 ring atoms and containing oxygen, sulphur or nitrogen atoms, all R 1 radicals being optionally substituted; and pharmaceutically acceptable salts and easily hydrolyzable esters thereof comprising reacting a compound of formula Vb ##STR44## in which Q 1 ' is Q 1 or ##STR45## R 2 being an alkanoyl, an aralkanoyl or an aroyl radical; Q 2 is as defined above; Y stands for chlorine, bromine or iodine; and R 3 stands for a straight or branched alkyl radical having from 1 to 6 carbon atoms, an aralkyl radical an alkanoyl- or aroylmethyl radical, an alkanoyl- or aroyl-oxyalkyl radical, an alkyloxymethyl or a cyanomethyl radical; with a compound of formula VII: R 1 -A-H, in which R 1 is as defined above and A represents oxygen or sulphur, yielding a compound of formula VIII: ##STR46## in which Q 1 ', Q 2 , R 1 and R 3 are as defined above, and A is oxygen or sulphur, which compound is thereafter subjected to a hydrolysis, if desired, and a compound of formula I, A being sulphur, optionally is oxidized to a compound of formula I, A being a sulfinyl radical; and the free acid can be transformed into a pharmaceutically acceptable salt or an easily hydrolyzable ester thereof.
Claim 33
Dependent Claim 37 words
A method according to claim 16, in which a compound of formula I, wherein Q 1 and/or Q 2 are ##STR47## is oxidized to a compound of formula I wherein Q 1 and/or Q 2 are oxygen.
Claim 34
Dependent Claim 40 words
A method according to claim 16 in which a compound of formula I, having a double bond between C-24 and C-25, is converted to a compound of formula I having a single bond between C-24 and C-25 by catalytic hydrogenation.
Claim 35
Dependent Claim 119 words
A method for the preparation of a compound of formula I as shown in claim 16 in which R 1 stands for an aroyl radical and A is sulphur, comprising reacting a compound of formula IV, ##STR48## in which Q 1 ', Q 2 and R 3 are as defined in claim 16, and the OH group at C-16 is α-oriented, with R 1 SSR 1 , thereby obtaining a compound of formula VIII shown in claim 16, in which A is sulphur and R 1 is aroyl and Q 1 ', Q 2 and R 3 are as defined in claim 16, which compound is thereafter transformed into a compound of formula I as claimed in claim 16.
Claim 36
Dependent Claim 159 words
A method for the preparation of compounds of formula I as shown in claim 16, comprising reacting a compound of formula IV, in which the hydroxyl group at C-16 is α-oriented and Q 1 ' is different from the group ##STR49## is reacted with a reactive derivative of an alkylsulphonic or arylsulphonic acid, to form a compound of the general formula IX: ##STR50## in which Q 2 , R 3 and the dotted line between C-24 and C-25 have the meaning as defined above, Q 1 ' stands for oxygen or the group ##STR51## R 2 being an alkanoyl, aralkanoyl or aroyl radical, and R 5 represents an alkylsulphonyl or arylsulphonyl radical, which compound is reacted with a compound R 1 -A-H, R 1 being as defined in claim 16 and A being oxygen or sulphur to form a compound of formula VIII, which compound is thereafter transformed into a compound of formula I as claimed in claim 16.
Claim 37
Dependent Claim 53 words
A method according to claim 16 where a compound of formula VIII in which Q 1 ' and Q 2 stand for the group ##STR52## or oxygen, and R 3 represents an unsubstituted or substituted benzyl radical, a cyanomethyl, alkanoylmethyl or aroylmethyl radical is converted into a compound of formula I by hydrogenation.
Claim 38
Dependent Claim 216 words
A method according to claim 16 comprising converting a compound of formula VIII in which Q 1 ', Q 2 , R 3 , and the dotted line between C-24 and C-25 have the meaning as defined above, A is oxygen, sulphur or a sulfinyl radical, and R 1 stands for a hydroxy-substituted alkyl radical, into a corresponding compound in which R 1 stands for a halo-substituted alkyl radical by treatment with halogenating agents, thereafter reacting the halo-substituted alkyl derivative of formula VIII with an aliphatic or aromatic alcohol, with an aliphatic or aromatic mercaptan, with ammonia or an aliphatic or aromatic amine, or with salts of lower alkanoic acids or benzoic acid, with silver or sodium fluoride, alkalimetal azides, nitrites; cyanides or thiocyanates, or with salts of lower thioalkanoic acids or thiobenzoic acid forming a compound of formula VIII in which Q 1 ', Q 2 , R 3 , A, and the dotted line between C-24 and C-25 have the meaning as defined above, and R 1 stands for an alkyl radical substituted by a fluorine atom, an alkyloxy, aralkyloxy, aryloxy, alkylthio, aralkylthio, arylthio, amino, alkylamino, dialkylamino, azido, nitro, cyano, thiocyano, alkanoyloxy, aralkanoyloxy, aroyloxy, alkanoylthio or aroylthio radical, which compound is thereafter transformed into a compound of formula I as claimed in claim 16.
Claim 39
Dependent Claim 13 words
A pharmaceutical composition containing as the active ingredient a compound of claim 1.
Claim 40
Dependent Claim 65 words
A pharmaceutical composition in dosage unit from for systemic treatment of bacterial infections in patients which comprises as a therapeutical ingredient at least one compound of claim 1, the therapeutically active compound being admixed with an atoxic, pharmaceutically acceptable carrier, and the dosage unit being between 100 to 1000 mg, preferably 100 to 500 mg, calculated as the free acid of the therapeutically active compound.
Claim 41
Dependent Claim 58 words
A pharmaceutical composition in dosage unit form for topical treatment of bacterial infections in patients which comprise as a therapeutical ingredient at least one compound of claim 1, the therapeutically active compound being admixed with an atoxic, pharmaceutically acceptable carrier, and the dosage unit being between 0.1 mg to 10 mg per sq. centimeter of the infected area.
Claim 42
Dependent Claim 18 words
A pharmaceutical composition as claimed in claim 24 wherein the dosage unit is in the form of tablets.
Claim 43
Dependent Claim 18 words
A pharmaceutical composition as claimed in claim 24 wherein the dosage unit is in the form of capsules.
Claim 44
Dependent Claim 19 words
A pharmaceutical composition as claimed in claim 25 wherein the dosage unit is in the form of a cream.
Claim 45
Dependent Claim 19 words
A pharmaceutical composition as claimed in claim 25 wherein the dosage unit is in the form of an ointment.
Claim 46
Dependent Claim 36 words
A pharmaceutical composition as claimed in claim 24 wherein the dosage unit is in the injectable form of preparation and contains from 50 to 500 mg, calculated as the free acid, of the therapeutically active compound.
Claim 47
Dependent Claim 32 words
A pharmaceutical composition as claimed in claim 24 wherein the dosage unit is a suspension for oral use and containing the therapeutically active compound in an amount of from 2 25 percent.
Claim 48
Dependent Claim 21 words
A pharmaceutical composition according to claim 23 in which the active ingredient is one of the compounds claimed in claim 8.
Claim 49
Dependent Claim 30 words
A pharmaceutical composition which comprises as the therapeutic ingredient a mixture of a compound of claim 1 and a corticosteroid selected from the group consisting of hydrocortisone, triamcinolone and fluocinolone.
Claim 50
Dependent Claim 23 words
A pharmaceutical composition according to claim 25, which comprises as the therapeutic ingredient a mixture of a compound of claim 1 and tetracycline.
Claim 51
Dependent Claim 37 words
A pharmaceutical composition according to claim 24, which comprises as the therapeutic ingredient a mixture of a compound of claim 1 and an antibiotic selected from the group consisting of penicillins, cephalosporins, rifamycin, erythromycin, lincomycin and clindamycin.
Claim 52
Dependent Claim 20 words
A method of treating bacterial infections which comprises administering into the body a member of the compounds of claim 1.
Claim 53
Dependent Claim 35 words
A method according to claim 36 in which the therapeutically active compound is administered by the oral route, in amounts from 200 to 4000 mg per day, preferably from 500 to 2000 mg per day.
Claim 54
Dependent Claim 17 words
A pharmaceutical composition in which the active ingredient is one of the compounds claimed in claim 9.
Claim 55
Dependent Claim 17 words
A pharmaceutical composition in which the active ingredient is one of the compounds claimed in claim 10.
Claim 56
Dependent Claim 17 words
A pharmaceutical composition in which the active ingredient is one of the compounds claimed in claim 11.
Claim 57
Dependent Claim 17 words
A pharmaceutical composition in which the active ingredient is one of the compounds claimed in claim 12.
Claim 58
Dependent Claim 17 words
A pharmaceutical composition in which the active ingredient is one of the compounds claimed in claim 13.
Claim 59
Dependent Claim 17 words
A pharmaceutical composition in which the active ingredient is one of the compounds claimed in claim 14.
Claim 60
Dependent Claim 17 words
A pharmaceutical composition in which the active ingredient is one of the compounds claimed in claim 15.
Claim 61
Dependent Claim 38 words
A method according to claim 21 wherein a compound of formula VIII in which R 3 represents a substituted or unsubstituted benzyl radical or a cyanomethyl radical is converted to a compound of formula I by catalytic hydrogenation.
Claim 62
Dependent Claim 35 words
A method according to claim 21 wherein a compound of formula VIII in which R 3 represents an alkanoylmethyl or aroylmethyl radical is converted to a compound of formula I by hydrogenation with nascent hydrogen.

References Cited (Backward Citations)

US3117059A Cited
US2937118A Cited
GB992276A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-11-28 1981-05-30 1981-11-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-11-28 1985-05-30 1985-11-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-11-28 1989-05-30 1989-11-29 $7700.00 Window Closed / Lapsed

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