- Atypical Carbapenem Antibiotics with Improved Activity Against Carbapenemase-Producing Acinetobacter baumannii
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The following invention deals with the design, preparation, evaluation, and use of carbapenem antibiotics with improved activity, relative to current commercially available carbapenem antibiotics, against infections involving multidrug resistant, carbapen
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- A catalytic asymmetric route to carbapenems
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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.
- Bodner, Micah J.,Phelan, Ryan M.,Townsend, Craig A.
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p. 3606 - 3609
(2011/03/17)
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- Efficient method for silylation of p-nitrobenzyl-2-diazoacetoacetate
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An efficient new method for the silylation of p-nitrobenzyl-2- diazoacetoacetate using hexamethyl disilane and iodine is presented. Copyright Taylor & Francis LLC.
- Tewari, Neera,Rai, Bishwa Prakash,Nizar, Hashim,Singh, Shailendra Kumar
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p. 211 - 214
(2007/10/03)
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- PROCESS FOR PREPARATION OF ESTERS OF 2-DIAZO-3-TRIMETHYLSILYLOXY-3-BUTENOIC ACID
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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.
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Page/Page column 12
(2008/06/13)
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- Stereoselective reactions. XX. Synthetic studies on optically active β-lactams. III. Stereocontrolled synthesis of chiral intermediate to (+)-thienamycin from D-glucose
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A chiral key intermediate (19a) for the synthesis of (+)-thienamycin was synthesized starting from D-glucose. The enol ether 13, obtained from the ketone 11 by Horner-Wittig reaction, was transformed to the corresponding methyl ester 16 by pyridinium chlorochromate oxidation or by employing the Wacker process. The ester 16 was further converted to the β-lactam 19a, which is a useful chiral precursor to (+)-thienamycin.
- Ikota,Yoshino,Koga
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p. 2201 - 2206
(2007/10/02)
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- Carbapenem intermediates
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A new process is provided for preparing the key carbapenem intermediates of the formula STR1 wherein R5 and R6 each independently represent hydrogen or methyl and R1 represents a conventional carboxyl-protecting group.
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- 3-[1-Hydroxyethyl]-4-carboxymethyl-azetidin-2-one
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In a process for the total synthesis of thienamycin from L-aspartic acid via intermediate III: STR1 there is disclosed a process for preparing III via STR2 wherein R is a protecting group.
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- Process for the preparation of 1-carbapenems and intermediates via silyl-substituted dithioacetals
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Disclosed is a process for the total synthesis of 1-carbapenem antibiotics (I) from L-aspartic acid via central intermediates II and III: STR1 wherein R is hydrogen, a pharmaceutically acceptable ester moiety or salt cation, or a readily removable blocking group; R6, R7 and R8 are, inter alia, independently selected from the group consisting of hydrogen, alkyl, alkenyl, aryl and aralkyl; R1' and Re are hydrogen, or a readily removable protecting group; Ra, Rb and Rc are selected from alkyl, aryl or aralkyl.
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- FROM PENICILLIN TO PENEM AND CARBAPENEM. SYNTHESIS OF 2-OXOCARBAPENAM DERIVATIVE
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Previously obtained 4-iodomethylazetidinone derivative (2a) is transformed via the trans-iodopropenylation method into the β-keto ester (8), which is thought to be an important precursor for the synthesis of the carbapenem derivatives.
- Hirai, Koichi,Iwano, Yuji,Fujimoto, Katsumi
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p. 3251 - 3254
(2007/10/02)
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- Process for the preparation of 1-carbapenems and intermediates via trithioorthoacetates
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Disclosed is a process for the total synthesis of 1-carbapenem antibiotics (I) from L-aspartic acid via intermediates II and III: STR1 wherein R is hydrogen, a pharmaceutically acceptable ester moiety or salt cation, or a readily removable blocking group; R6 and R7 are, inter alia, independently selected from the group consisting of hydrogen, alkyl, alkenyl, aryl and aralkyl; R1' is hydrogen or a protecting group; and Ra, Rb and Rc are independently selected from alkyl, aryl and aralkyl.
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- Process for the preparation of (2S)-tetrahydro-2α-methyl-6-oxo-4βα-carboxylic acid
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Disclosed is a process for preparing (2S)-tetrahydro-2α-methyl-6-oxo-4β-amino-2H-pyran-3α-carboxylic acid (I) which is useful in the synthesis of thienamycin. The process proceeds via a stereospecific reduction of the 2-acetyl-3-(R)-α-methylbenzylamino-2-pentenedioic acid diester (II). STR1 wherein R is, α-methylbenzyl, and R1 is lower alkyl having 1-6 carbon atoms or arylalkyl such as benzyl.
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- Process for the preparation of thienamycin and intermediates
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Disclosed is a process for the total synthesis of thienamycin from L-aspartic acid via intermediate III: STR1 R=H, blocking group or salt cation.
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- Process for the preparation of thienamycin and intermediates
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Disclosed is a process for the total synthesis of thienamycin from 4-allylazetidinone (IIIa) via STR1 L-aspartic acid (III): STR2 R=H, blocking group or salt cation.
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- Substituted benzenesulfonylazides
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Disclosed are substituted benzenesulfonylazides (I) which are useful as diazo transfer reagents. STR1 R°=C12 H25
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