156878-21-6Relevant articles and documents
Potential photoaffinity labels for tubulin. Synthesis and evaluation of diazocyclohexadienone and azide analogs of colchicine, combretastatin, and 3,4,5-trimethoxybiphenyl
Olszewski,Marshalla,Sabat,Sundberg
, p. 4285 - 4296 (1994)
Analogs of tubulin assembly inhibitors such as colchicine, combretastatin, and 3,4,5-trimethoxybiphenyl which incorporate a 6-diazo-2,4-cyclohexadienone (o-quinone diazide) ring have been synthesized and characterized. The compounds synthesized include 6-diazo-4-(2',3',4'-trimethoxyphenyl)cyclohexa-2,4-dien-1-one and its 3-methyl and 3-ethyl analogs (1a-c), 6-diazo-3-(2,3,4-trimethoxyphenyl)-2,4-cyclohexadien-1-one and its 4-methyl and 4-ethyl derivatives (2a-c), 4-[Z-2-(3',4',5'-trimethoxyphenyl)ethenyl]-6-diazocyclohexa-2,4-dienon e (3), 3-[Z-2-(3',4',5'-trimethoxyphenyl)ethenyl]-6-diazocyclohexa-2,4-dien-1 -one (4), the corresponding dihydro derivatives (5, 6) and two isomeric diazocyclohexadienones derived from N-acetylcolchinol (7, 8). Compounds in which the cyclohexadienone oxygen is approximately isostructural with carbonyl or hydroxy functions of the parent compounds exhibit good activity in the tubulin assembly inhibition assay. 2'-Alkyl-4'azido-3,4,5-trimethoxy-1,1'-biphenyls also show good activity as tubulin assembly inhibitors.
The: Ortho -substituent on 2,4-bis(trifluoromethyl)phenylboronic acid catalyzed dehydrative condensation between carboxylic acids and amines
Wang, Ke,Lu, Yanhui,Ishihara, Kazuaki
supporting information, p. 5410 - 5413 (2018/05/30)
2,4-Bis(trifluoromethyl)phenylboronic acid is a highly effective catalyst for dehydrative amidation between carboxylic acids and amines. Mechanistic studies suggest that a 2:2 mixed anhydride is expected to be the only active species, and the ortho-substituent of boronic acid plays a key role in preventing the coordination of amines to the boron atom of the active species, thus accelerating the amidation. This catalyst works for α-dipeptide synthesis.
