The stereoselectivity of the formation of macrocyclicstilbenes as well as the regioselectivity of their photocyclization are strongly influenced by the length of the connecting alkanediyl chain. The stereoisomers of the macrocyclicstilbenes and the corresponding diols are identified by chemical and spectroscopic means.
Highly Efficient Ring Closure of Aromatic Dialdehydes to Macrocyclic Allenes
作者:Marcus S. Brody、Robin M. Williams、M. G. Finn
DOI:10.1021/ja962868o
日期:1997.4.1
The one-pot double deoxygenation of simple alkyl- and polyether-tethered aromatic dialdehydes to give macrocyclic allenes has been accomplished in extraordinarily high yield without the need for slow-addition techniques, using a Ti(IV)-substituted ylide reagent and bis(trimethylsilyl)amide bases. Diastereoselective allene formation occurs when a binaphthyl unit is present in the substrate backbone
使用 Ti (IV) 取代的叶立德试剂和双 (三甲基甲硅烷基)酰胺碱。当底物主链中存在联萘单元时,会发生非对映选择性丙二烯形成,所得环状丙二烯通过 X 射线衍射表征。高效环化被认为是关于酰胺碱反离子的预组织和低浓度的 Wittig 型烯化环闭合的直接前体相结合的结果。
One-pot synthesis of bis(4,5-diphenylimidazol-2-yl-phenyl)glycols and evaluation of their antimicrobial activity
A new series of bis(4,5-diphenylimidazol-2-yl-phenyl)glycols were synthesized by reaction of bis(formylphenyl)glycols with benzil/benzoin and ammonium acetate in presence of iodine/acetic acid in ethanol. All newly synthesized compounds were characterised by IR, H-1, C-13 NMR, and MS data and tested for antimicrobial and antifungal activity.
Synthesis and biological evaluation of conformationally flexible as well as restricted dimers of monastrol and related dihydropyrimidones
A series of conformationally flexible and restricted dimers of monastrol as well as related dihydropyrimidones have been synthesized by employing one-pot Biginelli multicomponent reaction. These dimers have been evaluated for cytotoxic potency against selected human cancer cell lines and some of the compounds have exhibited more cytotoxic potency than the parent monastrol. Further. the DNA binding ability by thermal denaturation studies and antimicrobial activities of these compounds are also discussed. (C) 2011 Elsevier Masson SAS. All rights reserved.
Mondal, Rina; Mandal, Tapas K.; Mallik, Asok K., ARKIVOC, 2012, vol. 2012, # 9, p. 95 - 110,16