Design and synthesis of spiro-cyclopentenyl and spiro--dithiolanyl substituted pyrrolidine-5,5-trans-lactams as inhibitors of hepatitis C virus NS3/4A protease
摘要:
Using the pyrrolidine-5,5-trans-lactam template, we have designed small, neutral, mechanism-based inhibitors of hepatitis C NS3/4A protease. Compound 2b, with a spiro-cyclobutyl P1 substituent and an isopropyl carbonyl substituent at the lactam. nitrogen, has an IC50 value in the replicon cell-based assay of 3 muM. (C) 2003 Elsevier Science Ltd. All rights reserved.
A chiral oxazaborolidinone-promoted aldol reaction with a silyl ketene acetal from ethyl 1,3-dithiolane-2-carboxylate. Synthesis of acetate aldols in high enantiomeric purity
作者:Syun-ichi Kiyooka、Mostofa Abu Hena
DOI:10.1016/0957-4166(96)00265-0
日期:1996.8
Asymmetric synthesis of dithiolane aldols 3 was achieved in good yields by using silyl ketene acetal 1, derived from ethyl 1,3-dithiolane-2-carboxylate, in the chiral oxazaborolidinone (L-1 and D-2)-promoted aldol reaction and desulfurization of 3 resulted in production of acetate aldols 4 in high enantiomerc purity.
A short and efficient synthesis of N-Cbz-galantinic acid under promoter control on enantioselective acyclic stereoselection based on chiral oxazaborolidinone-promoted aldol reactions
作者:Syun-ichi Kiyooka、Kazuki Goh、Yuri Nakamura、Hironori Takesue、Mostofa A Hena
DOI:10.1016/s0040-4039(00)01124-2
日期:2000.8
An effective ‘promoter control’ on enantioselective acyclicstereoselection based on chiral oxazaborolidinone-promoted asymmetric aldol reactions has been found in the case of chiral N-protected α-amino aldehydes. An enantioselective synthesis of the title compound has been efficiently accomplished by using a sequence of the aldol reaction.
Enantioselective acyclic stereoselection under catalyst control. 2.1 Asymmetric synthesis of syn- and anti-1,3-diols incorporating an acetate equivalent by the chiral oxazaborolidinone-catalyzed aldol reaction
作者:Syun-ichi Kiyooka、Takafumi Yamaguchi、Hirofumi Maeda、Haruhide Kira、Mostofa Abu Hena、Michio Horiike
DOI:10.1016/s0040-4039(97)00701-6
日期:1997.5
The chiral oxazaborolidinone-catalysed aldol reaction of a silyl keteneacetal involving a dithiolane moiety with β-silyloxy aldehyde resulted in the production of syn- and anti-1,3-diols with complete stereoselection by the choice of the stereochemistry of the catalyst. This reaction is an elegant example of enantioselective acyclic stereoselection under catalyst control.
Enantioselective synthesis of a key intermediate aldehyde toward the polyene macrolide filipin III, based on a chiral oxazaborolidinone-promoted asymmetric aldol reaction
作者:Syun-ichi Kiyooka、Mostofa A. Hena、Fumitaka Goto
DOI:10.1016/s0957-4166(99)00278-5
日期:1999.7
A versatile preparation of an enantiopure aldehyde useful for the asymmetric totalsynthesis of filipinIII was developed using a chiral oxazaborolidinone-promoted asymmetric aldol reaction with a dithiolane silyl nucleophile. The sign and magnitude of the specific rotation of the aldehyde, (4R,5R)-2,2-dimethyl-5-formyl-4-pentyl-1,3-dioxane, were reconfirmed.
A Study Directed to the Asymmetric Synthesis of the Antineoplastic Macrolide Acutiphycin under Enantioselective Acyclic Stereoselection Based on Chiral Oxazaborolidinone-Promoted Asymmetic Aldol Reactions
作者:Syun-ichi Kiyooka、Mostofa A. Hena
DOI:10.1021/jo990342r
日期:1999.7.1
A shortening of the reaction path can be realized by using a series of the chiral oxazaborolidinone-promoted aldol reaction with respect to the practical synthesis of the (+)-acutiphycin seco acid derivative 5. The linear strategy is based on the utilization of five aldol reactions with a sequence of silyl nucleophiles, 7, 8, 35, 10, and 11, in the presence of stoichiometric amounts of the promoter, 1 or 2. The construction of the relative configuration between the stereogenic centers is diastereoselectively controlled by the stereochemistry of the promoter used in the enantioselective aldol reaction, which is nearly independent of that of the substrate (promoter control).