74288-40-7Relevant articles and documents
A catalytic asymmetric route to carbapenems
Bodner, Micah J.,Phelan, Ryan M.,Townsend, Craig A.
scheme or table, p. 3606 - 3609 (2011/03/17)
Image Presented Efficient syntheses of N-acetyl thienamycin and epithienamycin A in their readily deprotected form are reported where three contiguous stereocenters are established in a single catalytic asymmetric azetidinone-forming reaction. These examples are a template for synthesizing C-5/C-6 cis or trans carbapenems with independent control of the C-8 stereocenter. A library of oxidatively and sterochemically defined azetidinone precursors to a variety of naturally occurring carbapenems and potential biosynthetic intermediates has been prepared to facilitate studies of carbapenem antibiotic biosynthesis.
PROCESS FOR PREPARATION OF ESTERS OF 2-DIAZO-3-TRIMETHYLSILYLOXY-3-BUTENOIC ACID
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Page/Page column 13, (2008/06/13)
The present invention relates to a process for the preparation of esters of 2-diazo-3-trimethylsilyloxy-3-butenoic acid which comprises reacting a diazoacetoacetate with iodotrimethylsilane in the presence of an organic base, wherein iodotrimethylsilane is prepared by reacting hexamethyldisilane with iodine. The present invention further relates to converting such esters of 2-diazo-3-trimethylsilyloxy-3-butenoic acid to other compounds, such as a substituted diazoazetidinone, an azetidinone, or a bicyclo ketoester.
Simple and Condensed β-Lactams. Part 9. Elaboration of the 3-(1-Hydroxyethyl) Side Chains of Potential Intermediates of Carbapenem Antibiotics via the 2-Methyl-1,3-dioxolan-2-yl Group
Fetter, Jozsef,Lempert, Karoly,Kajtar-Peredy, Maria,Simig, Gyula
, p. 1135 - 1142 (2007/10/02)
Deketalization of the trans compounds methyl and ethyl (2RS,3RS)-1-(2,4-dimethoxybenzyl)-3-(2-methyl-1,3-dioxolan-2-yl)-4-oxoazetidine-2-carboxylates 5b and 5c, and of the cis isomer (6b) of the latter leads to 85:15 mixtures of the trans- and cis-compounds methyl (2RS,3RS)- and (2RS,3SR)-3-acetyl-1-(2,4-dimethoxybenzyl)-4-oxoazetidine-2-carboxylate (7a) and (8a), respectively of the corresponding ethyl esters (7b) and (8b).Sodium borohydride reduction of the mixture of the trans- and cis-esters (7b) and (8b) gives a mixture of the 1'-epimeric trans-compounds ethyl(2RS,3RS)-1-(2,4-dimethoxybenzyl)-3--4-oxazetidine-2-carboxylate (9b) and (10b).Similar mixtures of 1'-epimeric compounds of the types (9) and (10), carrying a variety of substituents attached to position 2 of their azetidine rings were obtained by successive deketalization and reduction of the corresponding trans-(5) and cis-(6) compounds or their mixtures, as well as by other methods.Ring closure of a mixture of the pair of the 1'-epimeric trans-compounds p-nitrobenzyl 2-diazo-4--4-oxo-azetidin-2-yl>-3-oxobutanoates (9n) and (10n) gave a mixture of the 1'-epimeric compounds p-nitrobenzyl 6--2,7-dioxo-(3RS,5RS,6SR)-carbapenam-3-carboxylates (11) and (12) which was converted into a mixture (13) of the 1'-epimeric bis-protected thienamycin analogues p-nitrobenzyl 2-(2-formylaminoethylthio)-6--7-oxo-(5RS,6SR)-carbapen-2-em-3-carboxylates.