80-11-5Relevant articles and documents
Scalable Synthesis of β-Lactamase Inhibitor QPX7728 by Sequential Nickel-Catalyzed Boron Insertion into a Benzofuran Substrate and Enantioselective Cyclopropanation of the Resulting Vinylboronate
Boyer, Serge H.,De Vries, André H. M.,Dielemans, J. A. Hubertus,Gnahn, Matthias,Gonzalez-De-Castro, Angela,Hecker, Scott J.,Lefort, Laurent,Sch?rghuber, Julia,Steinhofer, Stefan,Zhu, Zuolin
supporting information, (2021/10/01)
We report the scalable, high-yielding, and highly selective synthesis of the β-lactamase inhibitor QPX7728 featuring two key synthetic steps: nickel-catalyzed boron insertion of benzofuran 1 followed by enantioselective cyclopropanation of the resulting cyclic vinylboronate 2. The identification of the key reagents (catalyst and chiral auxiliary) for both steps relied on the use of high-throughput experimentation. Further optimization allowed for the cost-effective and scalable production of QPX7728.
Efficient, scalable and economical preparation of tris(deuterium)- and 13C-labelled N-methyl-N-nitroso-p-toluenesulfonamide (Diazald) and their conversion to labelled diazomethane
Shields, Samuel W.J.,Manthorpe, Jeffrey M.
, p. 674 - 679 (2015/01/16)
A method for the preparation of multi-gramme quantities of N-methyl-d3-N-nitroso-p-toluenesulfonamide (Diazald-d3) and N-methyl-13C-N-nitroso-p-toluenesulfonamide (Diazald-13C) and their conversion to diazomethane-d2 and diazomethane-13C, respectively, is presented. This approach uses robust and reliable chemistry, and critically, employs readily commercially available and inexpensivemethanol as the label source. Several reactions of labelled diazomethane are also reported, including alkene cyclopropanation, phenolmethylation and α-diazoketone formation, as well as deuteriumscrambling in the preparation of diazomethane-d2 and subsequent methyl esterification of benzoic acid.
Photochemical activities of n-nitroso carboxamides and sulfoximides and their application to DNA cleavage
Hwu, Jih Ru,Huang, Joseph Jen Tse,Tsai, Fu-Yuan,Tsay, Shwu-Chen,Hsu, Ming-Hua,Hwang, Kuo Chu,Horng, Jia-Cherng,Ho, Ja An Annie,Lin, Chun-Cheng
scheme or table, p. 8742 - 8750 (2010/03/31)
N-Nitroso compounds containing benzene, fluorene or fluorenone rings were synthesized. Photolysis of these compounds with 312-nm UV light provided the NO species, the presence of which was corroborated by use of an EPR method and of 2phenyl-4,4,5,5-tetramethylimidazolin-loxyl 3-oxide (PTIO) as a trapping agent. During irradiation of N-methylN-nitroso-9-fluorenone carboxamide (14c) in the absence of PTIO, it underwent decomposition followed by re-combination to give the heterocyclic nitric oxide radical 15. Incorporation of intercalating moieties endowed the Nnitroso compounds with DNA-cleaving ability through single-strand scission upon UV irradiation in a phosphate buffer (pH 5.0-8.0) under aerobic conditions.