85846-38-4Relevant articles and documents
Asymmetric synthesis of the C15-C32 fragment of alotamide and determination of the relative stereochemistry
Shi, Hao-Yun,Xie, Yang,Hu, Pei,Guo, Zi-Qiong,Lu, Yi-Hong,Gao, Yu,Huang, Cheng-Gang
, (2018)
Alotamide is a cyclic depsipetide isolated from a marine cyanobacterium and possesses a unique activation of calcium influx in murine cerebrocortical neurons (EC50 4.18 μM). Due to its limited source, the three stereocenters (C19, C28, and C30) in its polyketide fragment remain undetermined. In this study, the first asymmetric synthesis of its polyketide fragment was achieved. Four relative possible diastereomers were constructed with a boron-mediated enantioselective aldol reaction and Julia-Kocienski olefination as the key steps. Comparison of 13C NMR spectra revealed the relative structure of fragment C15-C32 of alotamide.
Synthesis and Cytotoxicity Evaluation of C4- and C5-Modified Analogues of the α,β-Unsaturated Lactone of Pironetin
Huang, David S.,Wong, Henry L.,Georg, Gunda I.
supporting information, p. 520 - 528 (2017/04/10)
Pironetin is a natural product with potent antiproliferative activity that forms a covalent adduct with α-tubulin via conjugate addition into the natural product's α,β-unsaturated lactone. Although pironetin's α,β-unsaturated lactone is involved in its binding to tubulin, the structure–activity relationship at different positions of the lactone have not been thoroughly evaluated. For a systematic evaluation of the structure–activity relationships at the C4 and C5 positions of the α,β-unsaturated lactone of pironetin, twelve analogues of the natural product were prepared by total synthesis. Modifying the stereochemistry at the C4 and/or C5 positions of the α,β-unsaturated lactone of pironetin resulted in loss of antiproliferative activity in OVCAR5 ovarian cancer cells. While changing the C4 ethyl substituent with groups such as methyl, propyl, cyclopropyl, and isobutyl were tolerated, groups with larger steric properties such as an isopropyl and benzyl groups were not.
A practical method for p -methoxybenzylation of hydroxy groups using 2,4,6-tris(p -methoxybenzyloxy)-1,3,5-triazine (TriBOT-PM)
Yamada, Kohei,Fujita, Hikaru,Kitamura, Masanori,Kunishima, Munetaka
, p. 2989 - 2997 (2013/11/06)
A new acid-catalyzed p-methoxybenzylating reagent, 2,4,6-tris(p- methoxybenzyloxy)-1,3,5-triazine (TriBOT-PM), has been developed. The reaction of acid- and alkali-labile alcohols with TriBOT-PM in the presence of a catalytic amount of various acids (TfOH, BF3·OEt2, CSA, etc.) afforded the corresponding p-methoxybenzyl ethers in good yields. Since TriBOT-PM is an air-stable crystalline solid and can be prepared from inexpensive materials, i.e. cyanuric chloride and anisyl alcohol, this route is of practical use. Georg Thieme Verlag Stuttgart, New York.
