Dechalcogenative Allylic Selenosulfide and Disulfide Rearrangements: Complementary Methods for the Formation of Allylic Sulfides in the Absence of Electrophiles. Scope, Limitations, and Application to the Functionalization of Unprotected Peptides in Aqueous Media
作者:David Crich、Venkataramanan Krishnamurthy、Franck Brebion、Maheswaran Karatholuvhu、Venkataraman Subramanian、Thomas K. Hutton
DOI:10.1021/ja072969u
日期:2007.8.1
Primary allylic selenosulfates (seleno Bunte salts) and selenocyanates transfer the allylic selenide moiety to thiols giving primary allylic selenosulfides, which undergo rearrangement in the presence of PPh3 with the loss of selenium to give allylically rearranged allyl alkylsulfides. This rearrangement may be conducted with prenyl-type selenosulfides to give isoprenyl alkylsulfides. Alkyl secondary
Allylic disulfide rearrangement and desulfurization method for the preparation of allylic sulfides
申请人:Crich David
公开号:US20070260041A1
公开(公告)日:2007-11-08
A method for the preparation of an allylic sulfide comprises contacting an activated sulfenyl compound of Formula (I) with a thiol of Formula (II) for a period of time sufficient to form an intermediate of Formula (III), and contacting the intermediate of Formula (III) with a thiophilic agent, in a polar solvent, to induce a [2,3]-sigmatropic rearrangement therein and thereby form an allylic sulfide of Formula (IV), with concomitant loss of a sulfur atom to the thiophilic agent, wherein in Formulas (I, II, II, and IV), X is S or SO
2
; Y is an aryl group, a substituted-aryl group, a heteroaryl group , or a substituted heteroaryl group; R
1
, R
2
, R
3
, R
4
, and R
5
are each independently H, a hydrocarbon moiety or a substituted hydrocarbon moiety; and R is an organic moiety.
METHODS FOR THE PREPARATION OF FUNCTIONALIZED PEPTIDES, PROTEINS AND CARBOHYDRATES AND THEIR CONJUGATES
申请人:Crich David
公开号:US20100222546A1
公开(公告)日:2010-09-02
The present invention relates to methods for ligation or derivatization of peptides, amino acids, and carbohydrates utilizing a chalcogen-based reactant, a peptide reactant, an amino acid reactant, a chalcogen-containing peptide reactant, a chalcogen-containing amino acid reactant, or a combination of two or more of the foregoing reactants substantially as described herein.
Allylic Disulfide Rearrangement and Desulfurization: Mild, Electrophile-Free Thioether Formation from Thiols
see text] Secondary and tertiary allylic 2-pyridyl and 2-benzothiazolyl disulfides react with thiol groups at room temperature to give secondary and tertiary allyl alkyl disulfides. On the addition of a phosphine, a desulfurative sigmatropic rearrangement takes place at room temperature to give thioethers.