675-20-7Relevant articles and documents
Rapid and Mild Lactamization Using Highly Electrophilic Triphosgene in a Microflow Reactor
Fuse, Shinichiro,Komuro, Keiji,Otake, Yuma,Masui, Hisashi,Nakamura, Hiroyuki
supporting information, p. 7525 - 7532 (2021/03/17)
Lactams are cyclic amides that are indispensable as drugs and as drug candidates. Conventional lactamization includes acid-mediated and coupling-agent-mediated approaches that suffer from narrow substrate scope, much waste, and/or high cost. Inexpensive, less-wasteful approaches mediated by highly electrophilic reagents are attractive, but there is an imminent risk of side reactions. Herein, a methods using highly electrophilic triphosgene in a microflow reactor that accomplishes rapid (0.5–10 s), mild, inexpensive, and less-wasteful lactamization are described. Methods A and B, which use N-methylmorpholine and N-methylimidazole, respectively, were developed. Various lactams and a cyclic peptide containing acid- and/or heat-labile functional groups were synthesized in good to high yields without the need for tedious purification. Undesired reactions were successfully suppressed, and the risk of handling triphosgene was minimized by the use of microflow technology.
An Integrated Cofactor/Co-Product Recycling Cascade for the Biosynthesis of Nylon Monomers from Cycloalkylamines
Sarak, Sharad,Sung, Sihyong,Jeon, Hyunwoo,Patil, Mahesh D.,Khobragade, Taresh P.,Pagar, Amol D.,Dawson, Philip E.,Yun, Hyungdon
, p. 3481 - 3486 (2020/12/17)
We report a highly atom-efficient integrated cofactor/co-product recycling cascade employing cycloalkylamines as multifaceted starting materials for the synthesis of nylon building blocks. Reactions using E. coli whole cells as well as purified enzymes produced excellent conversions ranging from >80 and 95 % into desired ω-amino acids, respectively with varying substrate concentrations. The applicability of this tandem biocatalytic cascade was demonstrated to produce the corresponding lactams by employing engineered biocatalysts. For instance, ?-caprolactam, a valuable polymer building block was synthesized with 75 % conversion from 10 mM cyclohexylamine by employing whole-cell biocatalysts. This cascade could be an alternative for bio-based production of ω-amino acids and corresponding lactam compounds.
The benzyl can be selectively removed by visible light or near visible light. Method for protecting allyl and propargyl group
-
Paragraph 0010, (2021/10/16)
The invention provides a method for selectively removing benzyl, allyl and propargyl protecting groups by visible light or near visible light, namely a substrate containing benzyl, allyl or propargyl protecting groups. The method has the advantages of simple operation, safe and clean visible light or near visible light as excitation conditions, cheap and easily available reagents, high reaction yield, high reaction chemistry and regional selectivity, and is suitable for selective removal of benzyl, allyl and propargyl protecting groups in various substrates.