A compound represented by the following formula (I′)
wherein X
1
is a methylene group, an ethylene group, a trimethylene group or a vinylene group, X
2
is a divalent group represented by the following formula A or B,
Y is an ethylene group or a vinylene group, m and n are each an integer of 0 to 7, which satisfy m+n=0 to 8, R1 and R2 are each independently a hydrogen atom, a methyl group or an ethyl group, provided that when X
1
is a methylene group, then X
2
is not a divalent group represented by the formula A, and when X
1
is a vinylene group, then X
2
is not a divalent group represented by the formula A. The compound is a stable capsinoid derivative, and is useful as an active ingredient of an external blood circulation enhancer or a cosmetic composition, a pharmaceutical composition, or a food composition.
Palladium-Catalyzed Stereoselective Intramolecular Oxidative Amidation of Alkenes in the Synthesis of 1,3- and 1,4-Amino Alcohols and 1,3-Diamines
作者:Andrei V. Malkov、Darren S. Lee、Maciej Barłóg、Mark R. J. Elsegood、Pavel Kočovský
DOI:10.1002/chem.201400123
日期:2014.4.22
An efficient and practical Pd‐catalyzed intramolecular oxidative allylic amidation provides facile access to derivatives of 1,3‐ and 1,4‐aminoalcohols and 1,3‐diamines. The method operates under mild reaction conditions (RT) with molecular oxygen (1 atm) as the sole reoxidant of Pd. Excellent diastereoselectivities were attained with substrates bearing a secondary stereogenic center
Asymmetric Total Syntheses of (+)-5-<i>epi</i>-Schisansphenin B and the Proposed Structure of (+)-15-Hydroxyacora-4(14),8-diene
作者:Day-Shin Hsu、Meng-Yu Wang、Jiun-Yi Huang
DOI:10.1021/acs.joc.1c02627
日期:2022.1.7
The asymmetric total syntheses of (+)-5-epi-schisansphenin B and the proposed structure of (+)-15-hydroxyacora-4(14),8-diene have been accomplished from 1,3-cyclopentadione (10) in eight synthetic steps. The enantioselective palladium-catalyzed redox-relay Heck alkenylation, the intramolecular Stetter reaction, and the regioselective Tiffeneau–Demjanov-type ring expansion were the pivotal steps in
A compound represented by the following formula (I′)
wherein X
1
is a methylene group, an ethylene group, a trimethylene group or a vinylene group, X
2
is a divalent group represented by the following formula A or B,
Y is an ethylene group or a vinylene group, m and n are each an integer of 0 to 7, which satisfy m+n=0 to 8, R1 and R2 are each independently a hydrogen atom, a methyl group or an ethyl group, provided that when X
1
is a methylene group, then X
2
is not a divalent group represented by the formula A, and when X
1
is a vinylene group, then X
2
is not a divalent group represented by the formula A. The compound is a stable capsinoid derivative, and is useful as an active ingredient of an external blood circulation enhancer or a cosmetic composition, a pharmaceutical composition, or a food composition.
Substrate-Directed Enantioselective Aziridination of Alkenyl Alcohols Controlled by a Chiral Cation
作者:Alexander Fanourakis、Nicholas J. Hodson、Arthur R. Lit、Robert J. Phipps
DOI:10.1021/jacs.3c00693
日期:——
Alkeneaziridination is a highly versatile transformation for the construction of chiral nitrogen-containing compounds. Inspired by the success of analogous substrate-directed epoxidations, we report an enantioselective aziridination of alkenyl alcohols, which enables asymmetric nitrene transfer to alkenes with varied substitution patterns, including those not covered by the current protocols. We believe