88002-47-5

Upstream product

• 873-55-2 sodium benzenesulfonate 
• 701-99-5 Phenoxyacetyl chloride 
• 35592-67-7 (3S,4S)-4-acetoxy-3-phenoxyacetamido-azetidin-2-one 

Downstream Products

• 140940-44-9 N-((2S,3R)-2-Allyl-2-benzenesulfonyl-4-oxo-azetidin-3-yl)-2-phenoxy-acetamide 
• 133789-03-4 N-((2R,3S)-2-But-3-enyl-4-oxo-azetidin-3-yl)-2-phenoxy-acetamide 
• 133789-07-8 N-[(2S,3R)-2-Benzenesulfonyl-1-(tert-butyl-dimethyl-silanyl)-2-dodecyl-4-oxo-azetidin-3-yl]-2-phenoxy-acetamide 
• 133789-08-9 N-((2S,3R)-2-Benzenesulfonyl-2-dodecyl-4-oxo-azetidin-3-yl)-2-phenoxy-acetamide 
• 150018-74-9 N-[(2S,3R)-2-Benzenesulfonyl-2-benzyl-1-(tert-butyl-dimethyl-silanyl)-4-oxo-azetidin-3-yl]-2-phenoxy-acetamide 
• 133789-10-3 N-[(2S,3R)-2-Benzenesulfonyl-1-(tert-butyl-dimethyl-silanyl)-2-(2-methoxy-ethyl)-4-oxo-azetidin-3-yl]-2-phenoxy-acetamide 
• 133789-20-5 N-[(2S,3R)-2-Benzenesulfonyl-1-(tert-butyl-dimethyl-silanyl)-4-oxo-2-pent-4-enyl-azetidin-3-yl]-2-phenoxy-acetamide 

Relevant academic research and scientific papers

Halide-terminated N-acyliminium ion-alkyne cyclizations: A new construction of carbacephem antibiotics

A series of 4-(3-alkynyl)azetidinones 13 was prepared from 4- (phenylsulfonyl)azetidine-2-one (9) and isopropyl glyoxylate hydrate. The 3- pentynyl (13a) and 4-phenyl-3-butynyl (13b) azetidinone acetates underwent 6- exo cyclization when treated with 3 equity of SnCl4 at 0 °C to provide 3- (1-chloroalkylidene)carbacephems 15a (65%) and 15b (33%) respectively. In contrast, the 3-butynyl (13d) and 4-(trimethylsilyl)-3-butynyl (13c) azetidinone acetates underwent 7-endo cyclization under similar conditions to give 1-azabicyclo[5.2.0]nonenes 14a (11%) and 14b (71%), respectively. Beginning with penicillin degradation product 18, the more elaborate 3- pentynyl azetidinone cyclization substrate 27 was prepared in seven steps. Exposure to 27 to 3 equiv of SnCl4 in CH2Cl2 at 0 °C for 6 h, followed by allowing the reaction mixture to warm to rt, provided the desired 3-(1- chloroethylidene)carbacephem 28 in 60% yield and high (>99%) enantiometric purity. Cleavage of the chloroethylidene group of 28 with ozone gave 3- hydroxy carbacephem 29 in 77% yield. Since this intermediate has been converted in three steps to loracarbef (3), a new formal total synthesis of this carbacephem antibiotic was concluded.

Stereoselective Synthesis of Cis-Substituted Azetidinones from Penicillin: a Formal Total Synthesis of Loracarbef

A new method for the synthesis of chiral azetidinones bearing a carbon-carbon bond at the 4-position is described.The preparation involves a stereoselective alkylation-reduction of a silylated 4-phenylsulfonyl azetidinone.The utility of this method was demonstrated by a formal total synthesis of loracarbef.

4-Norbornyl-sulfonyl azetidinone intermediates and process for preparing (S)-3-acylamino-4-substituted-2-azetidinones

Compounds having the formula STR1 can be prepared by reacting a compound having the formula STR2 with a Grignard reagent having the formula wherein R1 is phenylacetyl or phenoxyacetyl; R2 is a not readily enolyzable alkyl group, aryl