Generation and intramolecular cyclization of α-sulfinyl and α-sulfonyl radicals
摘要:
alpha-Phenylsulfinyl and alpha-Phenylsulfonyl radicals are generated by the reactions of alpha-chlorosulfoxides and alpha-chlorosulfones with tributyltin hydride, respectively. High reaction concentration (0.2 M) is required to ensure efficient generations of these radicals. The 5-exo-type intramolecular cyclizations of these radicals are studied. The cyclization is most successful when the olefin is terminally substituted with an ester group. The sulfinyl group only induces mild diastereoselectivity on the cyclization. (C) 1997 Elsevier Science Ltd.
A study of the functional group compatibility of sulfoximination methods
作者:Sylvaine Cren、Taryn C. Kinahan、Catharine L. Skinner、Heather Tye
DOI:10.1016/s0040-4039(02)00378-7
日期:2002.4
range of sulfoxides possessing functionalised side-chains using mesitylene sulfonyl hydroxylamine or iminoiodane reagents is discussed. The use of iminoiodane reagents possessing removable protecting groups (p-nosyl and Ses) is reported along with conditions for the deprotection of the sulfoximine adducts.
initial nucleophilic substitution at α-carbon of the sulfoxide to form aminomethyl p-toly sulfoxide, followed by rearrangement to the corresponding sulfenate, and subsequent attack of the amine at the sulfur atom of the sulfenate to form the final product. Meanwhile, a facile interconversion of alkoxymethyl p-toly sulfoxide and corresponding sulfenate was also observed.
A series of 6-(3-amino-2-hydroxypropoxy)-2(1H)-quinolinones has been synthesized and evaluated for positive inotropic activity on the canine heart. Some of these derivatives have a potent activity with none or negative chronotropic effect in isolated, blood-perfused dog heart preparations. They also display a high selectivity for positive inotropic effect over chronotropic and vasodilatory effects in anesthetized dogs. (+/-)-6-[2-Hydroxy-3-[(3-methoxybenzyl)amino]propoxy]-2(1H)-quinolinone (39) and (+/-)-6-[3-(3,4-dimethoxybenzyl)amino]-2-hydroxypropoxy]-2(1H)-quinolinone (40) were further investigated in conscious dogs. After iv administration, they did not affect heart rate or mean blood pressure at the dose producing a 50% increase in the peak of the first derivative of the left ventricular pressure. The compounds (39,OPC-18750, and 40,OPC-18790) are the most promising agents with desirable biological activities, and now are currently undergoing clinical evaluation.
Generation and intramolecular cyclization of α-sulfinyl and α-sulfonyl radicals
作者:Bor-Wen Ke、Chao-Hsiung Lin、Yeun-Min Tsai
DOI:10.1016/s0040-4020(97)00472-9
日期:1997.6
alpha-Phenylsulfinyl and alpha-Phenylsulfonyl radicals are generated by the reactions of alpha-chlorosulfoxides and alpha-chlorosulfones with tributyltin hydride, respectively. High reaction concentration (0.2 M) is required to ensure efficient generations of these radicals. The 5-exo-type intramolecular cyclizations of these radicals are studied. The cyclization is most successful when the olefin is terminally substituted with an ester group. The sulfinyl group only induces mild diastereoselectivity on the cyclization. (C) 1997 Elsevier Science Ltd.