83490-93-1Relevant articles and documents
Enantioselective Synthesis of Nitrogen-Nitrogen Biaryl Atropisomers via Copper-Catalyzed Friedel-Crafts Alkylation Reaction
Guo, Chang-Qiu,Liu, Ren-Rong,Lu, Chuan-Jun,Wang, Xiao-Mei,Xu, Qi,Zhang, De-Bing,Zhang, Peng
supporting information, p. 15005 - 15010 (2021/09/30)
Nitrogen-nitrogen bonds containing motifs are ubiquitous in natural products and bioactive compounds. However, the atropisomerism arising from a restricted rotation around an N-N bond is largely overlooked. Here, we describe a method to access the first enantioselective synthesis of N-N biaryl atropisomers via a Cu-bisoxazoline-catalyzed Friedel-Crafts alkylation reaction. A wide range of axially chiral N-N bisazaheterocycle compounds were efficiently prepared in high yields with excellent enantioselectivities via desymmetrization and kinetic resolution. Heating experiments showed that the axially chiral bisazaheterocycle products have high rotational barriers.
Tyrosine phosphatase inhibitors
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, (2008/06/13)
A compound of the formula (I): wherein X1 and X2 are the same or different and each is a bond or a spacer having 1 to 20 atom(s) in the main chain; one of R1 and R2 is a cycle group having substituent(s) selected from 1) an optionally substituted carboxy-C1-6 alkoxy group and 2) an optionally substituted carboxy-C1-6 aliphatic hydrocarbon group, wherein the cycle group optionally has additional substituent(s), and the other is an optionally substituted cycle group or a hydrogen atom; and R3, R4 and R5 are the same or different and each is a hydrogen atom or a substituent, or R4 may link together with R3 or R5 to form an optionally substituted ring; provided that when R3 is a hydrogen atom, R4 is a hydrogen atom and R5 is methyl, X2—R2 is not 4-cyclohexylphenyl; when R3 is 4-methoxyphenyl, R4 is a hydrogen atom and R5 is methyl, X2—R2 is not 4-methoxyphenyl; and when R1 or R2 is a hydrogen atom, the adjacent X1 or X2 is not a C1-7 alkylene; or a salt thereof exhibits a protein tyrosine phosphatase inhibitory action and is useful as a prophylactic or therapeutic agent for diabetes or the like.