Wang, Jing published the artcileMichael acceptor in gambogic acid-Its role and application for potent antitumor agents, Safety of 1H-Pyrazole-4-boronic acid, the publication is Bioorganic & Medicinal Chemistry Letters (2015), 25(14), 2844-2848, database is CAplus and MEDLINE.
Gambogic acid (GA), a natural product with unique structure, was reported to have broad antiproliferation activities against cancer cell lines. As a reactive Michael acceptor, the 10-position of GA is susceptible to nucleophiles, thus limiting its clin. application as an anticancer agent. Moreover, the 6-OH forms an intramol. hydrogen bond with 8-C=O, which can make the 9, 10 double bond more reactive to nucleophiles. In this essay, two strategies (A and B) were applied to solve the above-mentioned problems. Strategy A was to increase the steric hindrance of C-10 to reduce the activity of GA towards nucleophiles. Strategy B was to replace the hydroxyl of C-6 with other substituents based on the assumption that the intra-mol. hydrogen bond could increase the electrophilicity of C-10. Results showed the electrophilicity of C-10 disappeared as well as the antiproliferation activity against cancer cell lines by introducing a Me group at C-10. Strategy B showed that the electrophilicity of C-10 was reduced dramatically while maintained the activity by replacement of the hydroxyl of C-6 with neutral or basic groups.
Bioorganic & Medicinal Chemistry Letters published new progress about 763120-58-7. 763120-58-7 belongs to pyrazoles-derivatives, auxiliary class Pyrazole,Boronic acid and ester,Boronic Acids,Boronic acid and ester, name is 1H-Pyrazole-4-boronic acid, and the molecular formula is C7H7BClNO3, Safety of 1H-Pyrazole-4-boronic acid.
Referemce:
https://en.wikipedia.org/wiki/Pyrazole,
Pyrazoles – an overview | ScienceDirect Topics