合成路线1
该中间体在本合成路线中的序号:
(VII) The condensation of the cis-dibenzoyloxycyclopentene (I) with the lithium salt of 2-nitrovinyl(phenyl)sulfone (II) by means of a chiral palladium catalyst and PPh3 in THF gives the chiral isoxazoline-N oxide (III), which is deoxygenated by means of SnCl2 in acetonitrile, yielding the isoxazoline (IV). The solvolysis of (IV) with K2CO3 in methanol affords the methoxy compound (V), which is treated with Mo(CO)6 and boric acid in methanol to provide the chiral 2-hydroxy-3-cyclopentene-1-carboxylic acid methyl ester (VI). The reduction of (VI) with LiAlH4 in ether yields the hydroxymethyl derivative (VII), which is esterified with methyl chloroformate and BuLi in THF to afford the bis-carbonate (VIII). The condensation of (VIII) with 2-amino-6-chloropurine (IX) by means of a Pd catalyst in THF provides the carbocyclic purine (X), which is finally treated with NaOH in refluxing water to yield the target carbocyclic guanine.
【1】
Trost, B.M.; et al.; A novel Pd-catalyzed cycloalkylation to isoxazoline 2-oxides. Application for the asymmetric synthesis of carbanucleosides. J Am Chem Soc 1992, 114, 22, 8745.
|
中间体序号 |
中间体编号 |
品名 |
CAS号 |
分子式 |
供应商 |
用于合成 |
(I) |
37776 |
(1R,4S)-4-(benzoyloxy)-2-cyclopenten-1-yl benzoate
|
|
C19H16O4 |
详情 |
详情
|
(II) |
45393 |
lithium oxo[(phenylsulfonyl)methylene]-lambda(5)-azanolate
|
|
C7H6LiNO4S |
详情 |
详情
|
(III) |
45394 |
(3aS,6aR)-3-(phenylsulfonyl)-4,6a-dihydro-3aH-cyclopenta[d]isoxazol-2-ium-2-olate
|
|
C12H11NO4S |
详情 |
详情
|
(IV) |
45395 |
(3aS,6aR)-3-(phenylsulfonyl)-4,6a-dihydro-3aH-cyclopenta[d]isoxazole; (3aS,6aR)-4,6a-dihydro-3aH-cyclopenta[d]isoxazol-3-yl phenyl sulfone
|
|
C12H11NO3S |
详情 |
详情
|
(V) |
45396 |
(3aS,6aR)-3-methoxy-4,6a-dihydro-3aH-cyclopenta[d]isoxazole; (3aS,6aR)-4,6a-dihydro-3aH-cyclopenta[d]isoxazol-3-yl methyl ether
|
|
C7H9NO2 |
详情 |
详情
|
(VI) |
45397 |
methyl (1S,2R)-2-hydroxy-3-cyclopentene-1-carboxylate
|
|
C7H10O3 |
详情 |
详情
|
(VII) |
17671 |
(1R,5R)-5-(hydroxymethyl)-2-cyclopenten-1-ol
|
|
C6H10O2 |
详情 |
详情
|
(VIII) |
17672 |
[(1R,2R)-2-[(methoxycarbonyl)oxy]-3-cyclopenten-1-yl]methyl methyl carbonate
|
|
C10H14O6 |
详情 |
详情
|
(IX) |
11644 |
6-Chloro-9H-purin-2-amine; 6-Chloro-9H-purin-2-ylamine; 2-Amino-6-chloropurine
|
10310-21-1 |
C5H4ClN5 |
详情 | 详情
|
(X) |
45398 |
[(1S,4R)-4-(2-amino-6-chloro-9H-purin-9-yl)-2-cyclopenten-1-yl]methyl methyl carbonate
|
|
C13H14ClN5O3 |
详情 |
详情
|
合成路线2
该中间体在本合成路线中的序号:
(VII) The condensation of the chiral oxazolidinone (I) with the pentenoic anhydride (II) by means of n-BuLi in THF gives the N-pentenoyloxazolidinone (III), which is condensed with acrolein (IV) catalyzed by TiCl4 and (-)-spartein in dichloromethane, yielding the chiral adduct (V). The ring-closing metathesis of (V) by means of a Ru catalyst in dichloromethane affords the chiral cyclopentenol derivative (VI), which is reduced to the (R,R)-5-(hydroxymethyl)-2-cyclopenten-1-ol (VII) by means of LiBH4 in THF. The reaction of diol (VII) with Ac2O; with methyl chloroformate, TEA and DMAP; or with ethyl chloroformate and pyridine gives the diacetate (VIII), the cyclic carbonate (IX) or the dicarbonate (X), respectively. The condensation of (VIII), (IX) or (X) with 2-amino-6-chloropurine (XI) by means of Pd(PPh3)4 yields the carbocyclic purines (XII), (XIII) or (XIV), respectively. Finally, these compounds are hydrolyzed with aqueous NaOH to the target carbocyclic guanine.
【1】
Crimmins, M.T.; et al.; An efficient, general asymmetric synthesis of carbocyclic nucleosides: Application of an asymmetric aldol/ring-closing metathesis strategy. J Org Chem 2000, 65, 25, 8499.
|
中间体序号 |
中间体编号 |
品名 |
CAS号 |
分子式 |
供应商 |
用于合成 |
(I) |
14694 |
(S)-4-Benzyl-2-oxazolidinone; (4S)-4-Benzyl-1,3-oxazolan-2-one; (S)-(-)-4-Benzyl-2-oxazolidinone
|
90719-32-7 |
C10H11NO2 |
详情 | 详情
|
(II) |
17666 |
1,1-dimethylpropionic 4-pentenoic anhydride
|
|
C10H16O3 |
详情 |
详情
|
(III) |
17667 |
(4S)-4-benzyl-3-(4-pentenoyl)-1,3-oxazolidin-2-one
|
|
C15H17NO3 |
详情 |
详情
|
(IV) |
17668 |
acrylaldehyde; Acrolein
|
107-02-8 |
C3H4O |
详情 | 详情
|
(V) |
17669 |
(4S)-3-[(2S,3R)-2-allyl-3-hydroxy-4-pentenoyl]-4-benzyl-1,3-oxazolidin-2-one
|
|
C18H21NO4 |
详情 |
详情
|
(VI) |
17670 |
(4S)-4-benzyl-3-[[(1S,2R)-2-hydroxy-3-cyclopenten-1-yl]carbonyl]-1,3-oxazolidin-2-one
|
|
C16H17NO4 |
详情 |
详情
|
(VII) |
17671 |
(1R,5R)-5-(hydroxymethyl)-2-cyclopenten-1-ol
|
|
C6H10O2 |
详情 |
详情
|
(VIII) |
17674 |
[(1R,2R)-2-(acetoxy)-3-cyclopenten-1-yl]methyl acetate
|
|
C10H14O4 |
详情 |
详情
|
(IX) |
17673 |
(4aR,7aR)-4,4a,5,7a-tetrahydrocyclopenta[d][1,3]dioxin-2-one
|
|
C7H8O3 |
详情 |
详情
|
(X) |
17672 |
[(1R,2R)-2-[(methoxycarbonyl)oxy]-3-cyclopenten-1-yl]methyl methyl carbonate
|
|
C10H14O6 |
详情 |
详情
|
(XI) |
11664 |
4-Chloro-3-nitroquinoline
|
|
C9H5ClN2O2 |
详情 |
详情
|
(XII) |
45424 |
[(1S,4R)-4-(2-amino-6-chloro-9H-purin-9-yl)-2-cyclopenten-1-yl]methyl acetate
|
|
C13H14ClN5O2 |
详情 |
详情
|
(XIII) |
17650 |
[(1S,4R)-4-(2-amino-6-chloro-9H-purin-9-yl)-2-cyclopenten-1-yl]methanol
|
|
C11H12ClN5O |
详情 |
详情
|
(XIV) |
45398 |
[(1S,4R)-4-(2-amino-6-chloro-9H-purin-9-yl)-2-cyclopenten-1-yl]methyl methyl carbonate
|
|
C13H14ClN5O3 |
详情 |
详情
|
合成路线3
该中间体在本合成路线中的序号:
(VII) Alternatively, the (R,R)-5-(hydroxymethyl)-2-cyclopenten-1-ol (VII) can also be obtained as follows: The condensation of the chiral oxazolidinethione (XV) with the pentenoic anhydride (II) by means of n-BuLi in THF gives the N-pentenoyloxazolidinethione (XVI), which is condensed with crotonaldehyde (XVII) catalyzed by TiCl4 and (-)-spartein in dichloromethane, yielding the chiral adduct (XVIII). The ring-closing metathesis of (XVIII) by means of a Ru catalyst in dichloromethane affords the chiral cyclopentenol derivative (XIX), which is reduced to the target diol (VII) by means of LiBH4 in THF.
【1】
Crimmins, M.T.; et al.; An efficient, general asymmetric synthesis of carbocyclic nucleosides: Application of an asymmetric aldol/ring-closing metathesis strategy. J Org Chem 2000, 65, 25, 8499.
|
中间体序号 |
中间体编号 |
品名 |
CAS号 |
分子式 |
供应商 |
用于合成 |
(II) |
17666 |
1,1-dimethylpropionic 4-pentenoic anhydride
|
|
C10H16O3 |
详情 |
详情
|
(VII) |
17671 |
(1R,5R)-5-(hydroxymethyl)-2-cyclopenten-1-ol
|
|
C6H10O2 |
详情 |
详情
|
(XV) |
45425 |
(4S)-4-benzyl-1,3-oxazolidine-2-thione
|
|
C10H11NOS |
详情 |
详情
|
(XVI) |
41704 |
1-[(4R)-4-benzyl-2-thioxo-1,3-oxazolidin-3-yl]-4-penten-1-one
|
|
C15H17NO2S |
详情 |
详情
|
(XVII) |
22517 |
(E)-2-butenal
|
4170-30-3 |
C4H6O |
详情 | 详情
|
(XVIII) |
45426 |
(2S,3R,4E)-2-allyl-1-[(4S)-4-benzyl-2-thioxo-1,3-oxazolidin-3-yl]-3-hydroxy-4-hexen-1-one
|
|
C19H23NO3S |
详情 |
详情
|
(XIX) |
45427 |
[(4S)-4-benzyl-2-thioxo-1,3-oxazolidin-3-yl][(1S,2R)-2-hydroxy-3-cyclopenten-1-yl]methanone
|
|
C16H17NO3S |
详情 |
详情
|
合成路线4
该中间体在本合成路线中的序号:
(VIII) The cyclization of glyoxylic acid (I) with cyclopentadiene (II) gives the racemic hydroxylactone (III), which is acylated with Ac2O to yield acetoxy compound (rac)-(IV). The enzymatic optical resolution of (rac)-(IV) by means of Pseudomonas fluorescens affords the chiral hydroxylactone (-)-(V), which is reduced with LiAlH4 in refluxing THF to provide the lactol (VI). The oxidation of (VI) with NaIO4 in ethyl ether/water gives the chiral carbaldehyde (VII), which is reduced with NaBH4 in ethanol to afford the diol (VIII). The reaction of (VIII) with triphosgene by means of TEA in dichloromethane affords the cyclic carbonate (IX), which is condensed with chloropurine (X) by means of Pd(PPh3)4 in DMSO/THF to provide the adduct (XI). Finally, this compound is hydrolyzed with NaOH to afford the target (-)-carbovir.
【1】
Yu, J.; Olivo, H.F.; Practical enantiodivergent syntheses of both enantiomers of carbovir, 1592U89 and six-membered ring analogues. J Chem Soc - Perkins Trans I 1998, 3, 3, 391-2.
|
中间体序号 |
中间体编号 |
品名 |
CAS号 |
分子式 |
供应商 |
用于合成 |
(I) |
15618 |
2-Oxoacetic acid; Glyoxylic Acid
|
298-12-4 |
C2H2O3 |
详情 | 详情
|
(II) |
11183 |
1,3-Cyclopentadiene
|
|
C5H6 |
详情 |
详情
|
(III) |
55545 |
(3S,3aR,6aR)-3-hydroxy-3,3a,4,6a-tetrahydro-2H-cyclopenta[b]furan-2-one
|
|
C7H8O3 |
详情 |
详情
|
(IV) |
17679 |
(3S,3aR,6aR)-2-oxo-3,3a,4,6a-tetrahydro-2H-cyclopenta[b]furan-3-yl acetate
|
|
C9H10O4 |
详情 |
详情
|
(V) |
17678 |
(3S,3aR,6aR)-3-hydroxy-3,3a,4,6a-tetrahydro-2H-cyclopenta[b]furan-2-one
|
|
C7H8O3 |
详情 |
详情
|
(VI) |
55544 |
(3S,3aR,6aR)-3,3a,4,6a-tetrahydro-2H-cyclopenta[b]furan-2,3-diol
|
|
C7H10O3 |
详情 |
详情
|
(VII) |
17682 |
(1S,2R)-2-hydroxy-3-cyclopentene-1-carbaldehyde
|
|
C6H8O2 |
详情 |
详情
|
(VIII) |
17671 |
(1R,5R)-5-(hydroxymethyl)-2-cyclopenten-1-ol
|
|
C6H10O2 |
详情 |
详情
|
(IX) |
17673 |
(4aR,7aR)-4,4a,5,7a-tetrahydrocyclopenta[d][1,3]dioxin-2-one
|
|
C7H8O3 |
详情 |
详情
|
(X) |
11644 |
6-Chloro-9H-purin-2-amine; 6-Chloro-9H-purin-2-ylamine; 2-Amino-6-chloropurine
|
10310-21-1 |
C5H4ClN5 |
详情 | 详情
|
(XI) |
17650 |
[(1S,4R)-4-(2-amino-6-chloro-9H-purin-9-yl)-2-cyclopenten-1-yl]methanol
|
|
C11H12ClN5O |
详情 |
详情
|
合成路线5
该中间体在本合成路线中的序号:
(XXX) 4) The acylation of 4(S)-benzyloxazolidin-2-one (XXIV) with 4-pentenoyl pivaloyl anhydride (XXV) by means of NaH in THF gives 4(S)-benzyl-3-(4-pentenoyl)oxazolidin-2-one (XXVI), which is submitted to a diastereoselective syn aldol condensation with acrolein (XXVII), using dibutylboron triflate as catalyst, affording the aldol (XXVIII). The cyclization of (XXVIII) by means of the Grubbs catalyst in dichloromethane yields the cyclopentenol (XXIX), which is reduced with LiBH4 in THF/methanol to give the key intermediate 5(R)-(hydroxymethyl)-2-cyclopenten-1(R)-ol (XXX). The reaction of (XXX) with methyl chloroformate/pyridine/DMAP or methyl chloroformate/triethylamine/DMAP or acetic anhydride gives the diols (XXXI), (XXXII) and (XXXIII), respectively, each of which coupled with 2-amino-6-chloropurine (XXXIV) in the presence of NaH and palladium tetrakis(triphenylphosphine) in THF/DMSO, affords the purine intermediate (IX) already reported.
【1】
King, B.W.; Crimmins, M.T.; An efficient asymmetric approach to carbocyclic nucleosides: Asymmetric synthesis of 1592U89, a potent inhibitor of HIV reverse transcriptase. J Org Chem 1996, 61, 13, 4192-3.
|
【2】
Graul, A.; Castaner, J.; Leeson, P.A.; Abacavir Sulfate. Drugs Fut 1998, 23, 11, 1155-1167.
|
中间体序号 |
中间体编号 |
品名 |
CAS号 |
分子式 |
供应商 |
用于合成 |
(IX) |
17650 |
[(1S,4R)-4-(2-amino-6-chloro-9H-purin-9-yl)-2-cyclopenten-1-yl]methanol
|
|
C11H12ClN5O |
详情 |
详情
|
(XXIV) |
14694 |
(S)-4-Benzyl-2-oxazolidinone; (4S)-4-Benzyl-1,3-oxazolan-2-one; (S)-(-)-4-Benzyl-2-oxazolidinone
|
90719-32-7 |
C10H11NO2 |
详情 | 详情
|
(XXV) |
17666 |
1,1-dimethylpropionic 4-pentenoic anhydride
|
|
C10H16O3 |
详情 |
详情
|
(XXVI) |
17667 |
(4S)-4-benzyl-3-(4-pentenoyl)-1,3-oxazolidin-2-one
|
|
C15H17NO3 |
详情 |
详情
|
(XXVII) |
17668 |
acrylaldehyde; Acrolein
|
107-02-8 |
C3H4O |
详情 | 详情
|
(XXVIII) |
17669 |
(4S)-3-[(2S,3R)-2-allyl-3-hydroxy-4-pentenoyl]-4-benzyl-1,3-oxazolidin-2-one
|
|
C18H21NO4 |
详情 |
详情
|
(XXIX) |
17670 |
(4S)-4-benzyl-3-[[(1S,2R)-2-hydroxy-3-cyclopenten-1-yl]carbonyl]-1,3-oxazolidin-2-one
|
|
C16H17NO4 |
详情 |
详情
|
(XXX) |
17671 |
(1R,5R)-5-(hydroxymethyl)-2-cyclopenten-1-ol
|
|
C6H10O2 |
详情 |
详情
|
(XXXI) |
17672 |
[(1R,2R)-2-[(methoxycarbonyl)oxy]-3-cyclopenten-1-yl]methyl methyl carbonate
|
|
C10H14O6 |
详情 |
详情
|
(XXXII) |
17673 |
(4aR,7aR)-4,4a,5,7a-tetrahydrocyclopenta[d][1,3]dioxin-2-one
|
|
C7H8O3 |
详情 |
详情
|
(XXXIII) |
17674 |
[(1R,2R)-2-(acetoxy)-3-cyclopenten-1-yl]methyl acetate
|
|
C10H14O4 |
详情 |
详情
|
(XXXIV) |
11644 |
6-Chloro-9H-purin-2-amine; 6-Chloro-9H-purin-2-ylamine; 2-Amino-6-chloropurine
|
10310-21-1 |
C5H4ClN5 |
详情 | 详情
|
合成路线6
该中间体在本合成路线中的序号:
(XXX) 5) The water promoted condensation of glyoxylic acid (XXXV) with cyclopentadiene (XXXVI) gives the racemic cis-hydroxylactone (XXXVII), which is acetylated with acetic anhydride to the acetate (XXXVIII). The selective enzymatic hydrolysis of (XXXVIII) with Pseudomonas fluorescens lipase yields the pre (-)-enantiomer (XXXIX), which is reduced with LiAlH4 in refluxing THF, affording triol (XL). The oxidation of the vicinal glycol of (XL) with NaIO4 in ethyl ether/water yields the hydroxyaldehyde (XLI), which is reduced with NaBH4 in ethanol to give the key intermediate 5(R)-(hydroxymethyl)-2-cyclopenten-1(R)-ol (XXX). This compound, by reaction with triphosgene and triethylamine in dichloromethane, results in the cyclic carbonate intermediate (XXXII), already reported.
【1】
Yu, J.; Olivo, H.F.; Practical enantiodivergent syntheses of both enantiomers of carbovir, 1592U89 and six-membered ring analogues. J Chem Soc - Perkins Trans I 1998, 3, 3, 391-2.
|
【2】
Graul, A.; Castaner, J.; Leeson, P.A.; Abacavir Sulfate. Drugs Fut 1998, 23, 11, 1155-1167.
|
中间体序号 |
中间体编号 |
品名 |
CAS号 |
分子式 |
供应商 |
用于合成 |
(XXX) |
17671 |
(1R,5R)-5-(hydroxymethyl)-2-cyclopenten-1-ol
|
|
C6H10O2 |
详情 |
详情
|
(XXXII) |
17673 |
(4aR,7aR)-4,4a,5,7a-tetrahydrocyclopenta[d][1,3]dioxin-2-one
|
|
C7H8O3 |
详情 |
详情
|
(XXXV) |
15618 |
2-Oxoacetic acid; Glyoxylic Acid
|
298-12-4 |
C2H2O3 |
详情 | 详情
|
(XXXVI) |
11183 |
1,3-Cyclopentadiene
|
|
C5H6 |
详情 |
详情
|
(XXXVII) |
63844 |
(rac)-(3R*,3aS*,6aS*)-3-hydroxy-3,3a,4,6a-tetrahydro-2H-cyclopenta[b]furan-2-one
|
|
C7H8O3 |
详情 |
详情
|
(XXXVIII) |
17679 |
(3S,3aR,6aR)-2-oxo-3,3a,4,6a-tetrahydro-2H-cyclopenta[b]furan-3-yl acetate
|
|
C9H10O4 |
详情 |
详情
|
(XXXIX) |
17678 |
(3S,3aR,6aR)-3-hydroxy-3,3a,4,6a-tetrahydro-2H-cyclopenta[b]furan-2-one
|
|
C7H8O3 |
详情 |
详情
|
(XL) |
17681 |
(1S)-1-[(1S,2R)-2-hydroxy-3-cyclopenten-1-yl]-1,2-ethanediol
|
|
C7H12O3 |
详情 |
详情
|
(XLI) |
17682 |
(1S,2R)-2-hydroxy-3-cyclopentene-1-carbaldehyde
|
|
C6H8O2 |
详情 |
详情
|
合成路线7
该中间体在本合成路线中的序号:
(V) A new solid phase synthesis of abacavir has been reported:
Condensation of the chiral 4(R)-benzyl-3-(4-pentenoyl)oxazolidin-2-thione (I) with acrolein (II) by means of TiCl4 and DIEA gives the adduct (III), which was transformed into the chiral cyclopentene (IV) by catalytic ring-closing metathesis. The reductive removal of the chiral auxiliary with LiBH4 affords the chiral diol (V), which is selectively silylated with TBDMSCl providing the primary silyl ether (VI). Acylation of the secondary alcohol of (VI) with benzoic anhydride gives the benzoate (VII), which is desilylated with HF in acetonitrile yielding the allylic benzoate (VIII). Benzoate (VIII) is condensed with a p-nitrophenyl Wang carbonate resin (IX) by means of DIEA and DMAP affording the solid phase resin (X) which is condensed with 2-amino-6-chloropurine (XI) by means of a Pd catalyst furnishing the adduct (XII). Thermal condensation of (XII) with cyclopropylamine (XIII) yields the diaminopurine resin (XIV) which, after cleavage from the resin by a treatment with TFA in dichloromethane, gives directly abacavir.
【1】
Zuercher, W.J.; Crimmins, M.T.; Solid-phase synthesis of carbocyclic nucleosides. Org Lett 2000, 2, 8, 1065.
|
中间体序号 |
中间体编号 |
品名 |
CAS号 |
分子式 |
供应商 |
用于合成 |
(I) |
41704 |
1-[(4R)-4-benzyl-2-thioxo-1,3-oxazolidin-3-yl]-4-penten-1-one
|
|
C15H17NO2S |
详情 |
详情
|
(II) |
17668 |
acrylaldehyde; Acrolein
|
107-02-8 |
C3H4O |
详情 | 详情
|
(III) |
41705 |
(2S,3R)-2-allyl-1-[(4R)-4-benzyl-2-thioxo-1,3-oxazolidin-3-yl]-3-hydroxy-4-penten-1-one
|
|
C18H21NO3S |
详情 |
详情
|
(IV) |
41706 |
[(4R)-4-benzyl-2-thioxo-1,3-oxazolidin-3-yl][(1S,2R)-2-hydroxy-3-cyclopenten-1-yl]methanone
|
|
C16H17NO3S |
详情 |
详情
|
(V) |
17671 |
(1R,5R)-5-(hydroxymethyl)-2-cyclopenten-1-ol
|
|
C6H10O2 |
详情 |
详情
|
(VI) |
41707 |
(1R,5R)-5-([[tert-butyl(dimethyl)silyl]oxy]methyl)-2-cyclopenten-1-ol
|
|
C12H24O2Si |
详情 |
详情
|
(VII) |
41708 |
(1R,5R)-5-([[tert-butyl(dimethyl)silyl]oxy]methyl)-2-cyclopenten-1-yl benzoate
|
|
C19H28O3Si |
详情 |
详情
|
(VIII) |
41709 |
(1R,5R)-5-(hydroxymethyl)-2-cyclopenten-1-yl benzoate
|
|
C13H14O3 |
详情 |
详情
|
(XI) |
11644 |
6-Chloro-9H-purin-2-amine; 6-Chloro-9H-purin-2-ylamine; 2-Amino-6-chloropurine
|
10310-21-1 |
C5H4ClN5 |
详情 | 详情
|
(XII) |
17650 |
[(1S,4R)-4-(2-amino-6-chloro-9H-purin-9-yl)-2-cyclopenten-1-yl]methanol
|
|
C11H12ClN5O |
详情 |
详情
|
(XIII) |
12263 |
Cyclopropylamine; Cyclopropanamine
|
765-30-0 |
C3H7N |
详情 | 详情
|
合成路线8
该中间体在本合成路线中的序号:
(VII) An efficient asymmetric synthesis of abacavir has been reported: Acylation of the chiral oxazolidinone (I) with the mixed anhydride (II) by means of BuLi in THF gives the N-pentenoyloxazolidinone (III), which by condensation with acrolein (IV) catalyzed by TiCl4 and ()-spartein in dichloromethane yields the chiral adduct (V). The ring-closing metathesis of adduct (V) by means of the ruthenium catalyst (Cy3P)Cl2Ru=CHPh in dichloromethane affords the chiral cyclopentenol (VI), which is reduced to 5(R)-(hydroxymethyl)-2-cyclopenten-1(R)-ol (VII) by means of LiBH4 in THF. Reaction of diol (VII) with a) Ac2O, TEA and DMAP, b) methyl chloroformate, TEA and DMAP or c) methyl chloroformate, pyridine and DMAP gives a) the diacetate (VIII), b) the cyclic carbonate (IX) or c) the dicarbonate (X), respectively. The condensation of diacetate (VIII), cyclic carbonate (IX) or dicarbonate (X) with 2-amino-6-chloropurine (XI) by means of Pd(PPh3)4 yields the carbocyclic purines (XII), (XIII) or (XIV), respectively. Treatment of these chloro-purines (XII), (XIII) and (XIV) with cyclopropylamine (XV) in hot DMSO provides the corresponding cyclopropylaminopurine carbonate (XVI), abacavir or cyclopropylaminopurine acetate (XVII), respectively. Finally, the protecting groups of purines (XVI) and (XVII) are hydrolyzed with aqueous NaOH.
【1】
Crimmins, M.T.; et al.; An efficient, general asymmetric synthesis of carbocyclic nucleosides: Application of an asymmetric aldol/ring-closing metathesis strategy. J Org Chem 2000, 65, 25, 8499.
|
中间体序号 |
中间体编号 |
品名 |
CAS号 |
分子式 |
供应商 |
用于合成 |
(I) |
14694 |
(S)-4-Benzyl-2-oxazolidinone; (4S)-4-Benzyl-1,3-oxazolan-2-one; (S)-(-)-4-Benzyl-2-oxazolidinone
|
90719-32-7 |
C10H11NO2 |
详情 | 详情
|
(II) |
17666 |
1,1-dimethylpropionic 4-pentenoic anhydride
|
|
C10H16O3 |
详情 |
详情
|
(III) |
17667 |
(4S)-4-benzyl-3-(4-pentenoyl)-1,3-oxazolidin-2-one
|
|
C15H17NO3 |
详情 |
详情
|
(IV) |
17668 |
acrylaldehyde; Acrolein
|
107-02-8 |
C3H4O |
详情 | 详情
|
(V) |
17669 |
(4S)-3-[(2S,3R)-2-allyl-3-hydroxy-4-pentenoyl]-4-benzyl-1,3-oxazolidin-2-one
|
|
C18H21NO4 |
详情 |
详情
|
(VI) |
17670 |
(4S)-4-benzyl-3-[[(1S,2R)-2-hydroxy-3-cyclopenten-1-yl]carbonyl]-1,3-oxazolidin-2-one
|
|
C16H17NO4 |
详情 |
详情
|
(VII) |
17671 |
(1R,5R)-5-(hydroxymethyl)-2-cyclopenten-1-ol
|
|
C6H10O2 |
详情 |
详情
|
(VIII) |
17674 |
[(1R,2R)-2-(acetoxy)-3-cyclopenten-1-yl]methyl acetate
|
|
C10H14O4 |
详情 |
详情
|
(IX) |
17673 |
(4aR,7aR)-4,4a,5,7a-tetrahydrocyclopenta[d][1,3]dioxin-2-one
|
|
C7H8O3 |
详情 |
详情
|
(X) |
17672 |
[(1R,2R)-2-[(methoxycarbonyl)oxy]-3-cyclopenten-1-yl]methyl methyl carbonate
|
|
C10H14O6 |
详情 |
详情
|
(XI) |
11644 |
6-Chloro-9H-purin-2-amine; 6-Chloro-9H-purin-2-ylamine; 2-Amino-6-chloropurine
|
10310-21-1 |
C5H4ClN5 |
详情 | 详情
|
(XII) |
45424 |
[(1S,4R)-4-(2-amino-6-chloro-9H-purin-9-yl)-2-cyclopenten-1-yl]methyl acetate
|
|
C13H14ClN5O2 |
详情 |
详情
|
(XIII) |
17650 |
[(1S,4R)-4-(2-amino-6-chloro-9H-purin-9-yl)-2-cyclopenten-1-yl]methanol
|
|
C11H12ClN5O |
详情 |
详情
|
(XIV) |
45398 |
[(1S,4R)-4-(2-amino-6-chloro-9H-purin-9-yl)-2-cyclopenten-1-yl]methyl methyl carbonate
|
|
C13H14ClN5O3 |
详情 |
详情
|
(XV) |
12263 |
Cyclopropylamine; Cyclopropanamine
|
765-30-0 |
C3H7N |
详情 | 详情
|
(XVI) |
49433 |
[(1S,4R)-4-[2-amino-6-(cyclopropylamino)-9H-purin-9-yl]-2-cyclopenten-1-yl]methyl acetate
|
|
C16H20N6O2 |
详情 |
详情
|
(XVII) |
49434 |
[(1S,4R)-4-[2-amino-6-(cyclopropylamino)-9H-purin-9-yl]-2-cyclopenten-1-yl]methyl methyl carbonate
|
|
C16H20N6O3 |
详情 |
详情
|
合成路线9
该中间体在本合成路线中的序号:
(VII) Alternatively, 5(R)-(hydroxymethyl)-2-cyclopenten-1(R)-ol (VII) can also be obtained as follows: Acylation of the chiral oxazolidinethione (XIX) with the mixed anhydride (II) by means of BuLi in THF gives the N-pentenoyl-oxazolidinethione (XX), which by condensation with crotonaldehyde (XXI) catalyzed by TiCl4 and ()-spartein in dichloromethane yields the chiral adduct (XXII). The ring-closing metathesis of (XXII) by means of the ruthenium catalyst in dichloromethane affords the chiral cyclopentenol derivative (XXIII), which is reduced to the target diol (VII) by means of LiBH4 in THF.
【1】
Crimmins, M.T.; et al.; An efficient, general asymmetric synthesis of carbocyclic nucleosides: Application of an asymmetric aldol/ring-closing metathesis strategy. J Org Chem 2000, 65, 25, 8499.
|
中间体序号 |
中间体编号 |
品名 |
CAS号 |
分子式 |
供应商 |
用于合成 |
(II) |
17666 |
1,1-dimethylpropionic 4-pentenoic anhydride
|
|
C10H16O3 |
详情 |
详情
|
(VII) |
17671 |
(1R,5R)-5-(hydroxymethyl)-2-cyclopenten-1-ol
|
|
C6H10O2 |
详情 |
详情
|
(XIX) |
45425 |
(4S)-4-benzyl-1,3-oxazolidine-2-thione
|
|
C10H11NOS |
详情 |
详情
|
(XX) |
41704 |
1-[(4R)-4-benzyl-2-thioxo-1,3-oxazolidin-3-yl]-4-penten-1-one
|
|
C15H17NO2S |
详情 |
详情
|
(XXI) |
22517 |
(E)-2-butenal
|
4170-30-3 |
C4H6O |
详情 | 详情
|
(XXII) |
45426 |
(2S,3R,4E)-2-allyl-1-[(4S)-4-benzyl-2-thioxo-1,3-oxazolidin-3-yl]-3-hydroxy-4-hexen-1-one
|
|
C19H23NO3S |
详情 |
详情
|
(XXIII) |
45427 |
[(4S)-4-benzyl-2-thioxo-1,3-oxazolidin-3-yl][(1S,2R)-2-hydroxy-3-cyclopenten-1-yl]methanone
|
|
C16H17NO3S |
详情 |
详情
|