67638-32-8Relevant academic research and scientific papers
Ni-Catalyzed asymmetric reduction of α-keto-β-lactams: via DKR enabled by proton shuttling
Wang, Fangyuan,Tan, Xuefeng,Wu, Ting,Zheng, Long-Sheng,Chen, Gen-Qiang,Zhang, Xumu
supporting information, p. 15557 - 15560 (2020/12/30)
Chiral α-hydroxy-β-lactams are key fragments of many bioactive compounds and antibiotics, and the development of efficient synthetic methods for these compounds is of great value. The highly enantioselective dynamic kinetic resolution (DKR) of α-keto-β-lactams was realized via a novel proton shuttling strategy. A wide range of α-keto-β-lactams were reduced efficiently and enantioselectively by Ni-catalyzed asymmetric hydrogenation, providing the corresponding α-hydroxy-β-lactam derivatives with high yields and enantioselectivities (up to 92% yield, up to 94% ee). Deuterium-labelling experiments indicate that phenylphosphinic acid plays a pivotal role in the DKR of α-keto-β-lactams by promoting the enolization process. The synthetic potential of this protocol was demonstrated by its application in the synthesis of a key intermediate of Taxol and (+)-epi-Cytoxazone. This journal is
Microwave-mediated synthesis of 3-unsubstituted β-lactams with aqueous trimethylborane
Yadav, Ram Naresh,Banik, Indrani,Banik, Bimal Krishna
, p. 1381 - 1384 (2020/06/27)
A new microwave-induced method for the preparation of 3-unsubstituted β-lactams is explored via aqueous trimethylborane-mediated reaction of the corresponding xanthates.
Bismuth nitrate-induced microwave-mediated deglycosylation of O-glycosides: Synthesis of enantiopure 3-hydroxy β-lactams
Banik, Indrani,Yadav, Ram Naresh,Becker, Fredrick F.,Banik, Bimal Krishna
, p. 1373 - 1376 (2020/06/27)
Bismuth nitrate-induced microwave-mediated cleavages of O-glycosidic bond in β-lactams are achieved to afford their corresponding hydroxyl derivatives in excellent yields.
Reactions of acid chlorides/ketenes with 2-substituted 4,5-dihydro-4,4- dimethyl-1,3-thiazoles: Formation of penam derivatives
Shi, Junxing,Linden, Anthony,Heimgartner, Heinz
, p. 1462 - 1481 (2013/09/02)
Addition reactions of acid chlorides with various 2-substituted 4,5-dihydro-4,4-dimethyl-5-(methylsulfanyl)-1,3-thiazoles under basic conditions were studied. Two kinds of products were obtained from these additions, β-lactams and non-β-lactam adducts. When the reaction was carried out with 4,5-dihydro-1,3-thiazoles with a Ph substituent at C(2), the reaction proceeded via formal [2+2] cycloaddition and led to the correspoding β-lactam. On the other hand, acid chlorides and 4,5-dihydro-1,3-thiazoles bearing an α-H-atom at the C(2)-substituent underwent C(α)- and/or N-addition reactions and furnished non-β-lactam adducts, i.e., C(α)- and/or N-acylated 1,3-thiazolidines. The attempted transformations of sulfonyl esters of exo-6-hydroxy penams to endo-6-azido penams failed, although they were successful with mono-β-lactams under the same conditions. Copyright
A novel asymmetric synthesis of 3-(1H-pyrrol-1-yl)-substituted β-lactams via a bismuth nitrate-catalyzed reaction
Shaikh, Aarif L.,Banik, Bimal K.
scheme or table, p. 839 - 844 (2012/06/16)
The reaction of racemic α-keto β-lactams 5a-5c with the commercially available chiral compound trans-4-hydroxy-L-proline (6) in the presence of a catalytic amount of Bi(NO3)3·5 H 2O in EtOH gave a diastereoisomer mixture o
Synthesis of 3-acetoxyazetidin-2-ones and 3-hydroxyazetidin-2-ones with antifungal and antibacterial activity
Walsh,Meegan,Prendergast,Al Nakib
, p. 989 - 1000 (2007/10/03)
The synthesis of a series of 3-acetoxyazetidin-2-ones 3a-n and 3-hydroxyazetidin-2-ones 6a-j is reported together with the antibacterial and antifungal evaluation of these compounds. An additional series of 3-acetoxyazetidin-2-ones 11a-h which possess a free carboxylic acid group on the N-1 aryl ring were obtained by treatment of suitably substituted Schiff bases 10a-h with acetoxyacetyl chloride. The novel bicyclic structures 7-acetoxy-6-phenyl-5-thia-1-azabicyclo[4.2.0]octan-8-one 13 and 7-hydroxy-6-phenyl-5-thia-1-azabicyclo[4.2.0]octan-8-one 14 were also obtained. Many of the compounds displayed antifungal activity in vitro when evaluated against the pathogenic fungi Cryptococcus neoformans, Candida albicans, Candida tropicalis, Candida parapsilosis, Candida glabrata, and Trichosporon cutaneum, while 3-acetoxyazetidin-2-ones 11a-h containing a free carboxylic acid group on the N-1 aryl ring displayed antibacterial activity against Staphylococcus aureus, Proteus vulgaris, Pseudomonas aeruginosa, Bacillus subtilis, Klebsiella aerogenes and Escherischia coli.
STEREOSELECTIVE ANNELATION OF TRIMETHYLSILOXYACETIC ACIDS AND IMINES INTO 3-HYDROXY-β-LACTAMS
Cossio, Fernando P.,Palomo, Claudio
, p. 4239 - 4242 (2007/10/02)
Stereoselective synthesis of variously substituted 3-hydroxy-β-lactams can be achieved by the annelation of Schiff bases with trimethylsiloxyacetic acids promoted by phenyl dichlorophosphate reagent.A potential synthesis of N-unsubstituted β-lactams is ma
