已经开发出一种通过可切换的 C-芳基化/内酯化或 SNA Ar 反应从各种软亲核试剂和邻羟基乙酸酯合成取代异香豆素、黄酮和异喹啉二酮衍生物的一锅策略。这种碱介导的方案在无过渡金属的条件下进行,并从易于制备或市售的 1,3-二羰基和α -EWG 取代的羰基化合物中选择性地以 13-98% 的产率提供各种杂芳烃。该合成效用在潜在抗HIV 和抗 HIV 药物的合成中得到了进一步证明。-冠状病毒衍生物和COX-2抑制剂。此外,还进行了详细的实验和计算研究,以提供对反应机理的深入理解和有力支持。
Structural Studies on Bioactive Compounds. 32. Oxidation of Tyrphostin Protein Tyrosine Kinase Inhibitors with Hypervalent Iodine Reagents
摘要:
Hydroxylated styrenes (tyrphostins) undergo oxidation by hypervalent iodine oxidants such as [(diacetoxy)iodo]benzene (DAIB) to give a range of products depending on the structure of the phenolic substrate, the solvent, the oxidant stoichiometry, and the purification strategy. Conditions have been developed to modify the phenolic component of the tyrphostin without affecting the appended substituted-vinyl moiety. Novel products include: unstable 2-acyloxy-2-methoxy-4-(substituted-vinyl)cyclohexadienones and their rearrangement products 2-acyloxy-4-hydroxy-3 -methoxy-1-(substituted-vinyl)benzenes; phenyliodoniophenolates and their rearrangement products iodophenoxytyrphostins; and 3,3'-dialkoxy-2,2'-dihydroxy-5,5'-di(substituted-vinyl)biphenyls. None of these oxidation products displayed enhanced activity in vitro in the NCI 60-cell line panel or in a panel of human breast cancer cell lines, compared to their tyrphostin precursors. The inhibitory activity of three representative tyrphostins (3e,n, 28) was not modulated by aerobic/anaerobic conditions in MCF-7 and MDA 468 cells and was independent of EGFR status in clones of ZR75B cells transfected with this receptor. Basal growth of MCF-7 cells was unaffected by co-administration of the growth factors EGF, TGF-alpha, IGF-I, and IGF-II, and the new agents did not inhibit EGFR and c-erbB2 autaphosphorylation in cell lysates from MDA 468 or SkBr3 cells, respectively, suggesting that receptor tyrosine kinases are not targets for these compounds. Growth stimulation by the tyrphostin 3n in the ER+ breast cell lines MCF-7, T47D, and ZR75-1 was abolished by 1 mu M tamoxifen, suggesting that this compound has estrogen agonist activity.