Synthesis of chiral diamines using novel 2-trichloromethyloxazolidin-4-one precursors derived from 5-oxo-proline and proline
摘要:
Efficient syntheses of chiral vicinal diamines derived from (S)-oxo-proline and (S)-proline are described. The novel diastereomerically pure precursor (2R,5S)-2-trichloromethyl-1-aza-3-oxabicyclo-[3.3.0]-octan-4,8-dione 3 and its enantiomer are readily available by reaction of the inexpensive enantiomers of 5-oxo-proline with chloral. Compound 3 reacts with primary and secondary amines to afford the 5-oxo-prolylamides 4 in quantitative yield. In contrast, the (S)-proline-derived precursor (2R,5S)-2-trichloromethyl-1-aza-3-oxabicyclo[3.3.0]octan-4-one 6 gave (S)-N-formylprolylamides 9 and/or (S)-prolylamides 8 depending on the reaction conditions. Upon reduction with LiAlH4, amides 4 and 9 afforded the proline-derived (S)-2-(alkylaminomethyl)pyrrolidines 1 and (S)-N- methyl-2-(alkylaminomethyl)-pyrrolidines 5 in 70-90% yields. (C) 2002 Elsevier Science Ltd. All rights reserved.
Pyrazolo [3,4-B] pyridine Compounds and Their Use as Phosphodiesterase Inhibitors
申请人:Allen George David
公开号:US20070111995A1
公开(公告)日:2007-05-17
The invention provides pyrazolo[3,4-b]pyridine compounds of formula (I) having a —C(O)—NH—C(R
4
)(R
5
)-aryl substituent at the 5-position of the pyrazolo[3,4-b]pyridine ring system wherein at least one of R
4
and R
5
is not a hydrogen atom (H) compound or a salt thereof:
wherein Ar has the sub-formula (x) or (z).
These compounds are useful as inhibitors of PDE4.
Synthesis of chiral diamines using novel 2-trichloromethyloxazolidin-4-one precursors derived from 5-oxo-proline and proline
作者:Mohamed Amedjkouh、Per Ahlberg
DOI:10.1016/s0957-4166(02)00579-7
日期:2002.10
Efficient syntheses of chiral vicinal diamines derived from (S)-oxo-proline and (S)-proline are described. The novel diastereomerically pure precursor (2R,5S)-2-trichloromethyl-1-aza-3-oxabicyclo-[3.3.0]-octan-4,8-dione 3 and its enantiomer are readily available by reaction of the inexpensive enantiomers of 5-oxo-proline with chloral. Compound 3 reacts with primary and secondary amines to afford the 5-oxo-prolylamides 4 in quantitative yield. In contrast, the (S)-proline-derived precursor (2R,5S)-2-trichloromethyl-1-aza-3-oxabicyclo[3.3.0]octan-4-one 6 gave (S)-N-formylprolylamides 9 and/or (S)-prolylamides 8 depending on the reaction conditions. Upon reduction with LiAlH4, amides 4 and 9 afforded the proline-derived (S)-2-(alkylaminomethyl)pyrrolidines 1 and (S)-N- methyl-2-(alkylaminomethyl)-pyrrolidines 5 in 70-90% yields. (C) 2002 Elsevier Science Ltd. All rights reserved.