Chemoenzymatic synthesis of acetyl (R)-(+)- and (S)-(−)-cycloserine
摘要:
The two enantiomers of acetyl cycloserine 8, the immediate precursors of the chiral forms of cycloserine 1, were prepared in enantiomeric excess higher than 98% by means of lipase-catalyzed hydrolysis of 3-benzyloxy-4-hydroxy-DELTA2-isoxazoline butyrate (+/-)-5. Among the five lipases tested, lipase from Chromobacterium viscosum was by far the most selective catalyst. Since the enantiomeric ratio (E) of the reaction was higher than 100, the hydrolysis spontaneously stopped at 50% conversion to yield (R)-3-benzyloxy-4-hydroxy-DELTA2-isoxazoline [(R)-(+)-4] and (S)-3-benzyloxy-4-hydroxy-DELTA2-isoxazoline butyrate [(S)-(-)-5] in almost enantiomerically pure form. Intermediates (R)-(+)-4 and (S)-(-)-5 were transformed into the enantiomers of acetyl cycloserine through a four step sequence. This strategy constitutes a valid alternative to the previously reported procedures.
Benzamido and acetamido 4-amino-3-isoxazolidones and alkylated derivatives
申请人:MERCK &
公开号:US02845432A1
公开(公告)日:1958-07-29
STRUCTURE AND REACTIONS OF CYCLOSERINE<sup>1</sup>
作者:Phil H. Hidy、E. B. Hodge、Vernon V. Young、Roger L. Harned、Glenn A. Brewer、W. F. Phillips、W. F. Runge、Homer E. Stavely、A. Pohland、H. Boaz、H. R. Sullivan
DOI:10.1021/ja01613a106
日期:1955.4
Mitsui; Imaizumi, Nippon Kagaku Zasshi, 1957, vol. 78, p. 812
作者:Mitsui、Imaizumi
DOI:——
日期:——
Chemoenzymatic synthesis of acetyl (R)-(+)- and (S)-(−)-cycloserine
作者:Marco de Amici、Carlo de Micheli、Francesca Cateni、Giacomo Carrea、Gianluca Ottolina
DOI:10.1016/s0957-4166(00)80156-1
日期:1993.5
The two enantiomers of acetyl cycloserine 8, the immediate precursors of the chiral forms of cycloserine 1, were prepared in enantiomeric excess higher than 98% by means of lipase-catalyzed hydrolysis of 3-benzyloxy-4-hydroxy-DELTA2-isoxazoline butyrate (+/-)-5. Among the five lipases tested, lipase from Chromobacterium viscosum was by far the most selective catalyst. Since the enantiomeric ratio (E) of the reaction was higher than 100, the hydrolysis spontaneously stopped at 50% conversion to yield (R)-3-benzyloxy-4-hydroxy-DELTA2-isoxazoline [(R)-(+)-4] and (S)-3-benzyloxy-4-hydroxy-DELTA2-isoxazoline butyrate [(S)-(-)-5] in almost enantiomerically pure form. Intermediates (R)-(+)-4 and (S)-(-)-5 were transformed into the enantiomers of acetyl cycloserine through a four step sequence. This strategy constitutes a valid alternative to the previously reported procedures.
The nuclear magnetic resonance and mass spectra of derivatives of cycloserine
作者:G.W.A. Milne、L.A. Cohen
DOI:10.1016/s0040-4020(01)83287-7
日期:1967.1
parameters of the ABX system. Variation in the site of acylation is considered explicable in terms of kinetic vs. thermodynamic control. The mass spectra of various derivatives of cycloserine are shown to be compatible with the assigned structures. Some unusual modes of fragmentation of the 4-amino-3-isoxazolidone system are discussed.