Synthesis of Fischer type-carbene complexes containing a coordinated thioimidate structural motif.

This paper describes a tandem strategy to synthesize a series of new Fischer carbene complexes [(CO)(4)M=C[N-(CH(2))(4)-]CH=C(NRR')(SR'); M = Cr, W; R = Ar, R' = Me, -(CH(2))(2)-] with a thioimide or thiazoline fragment, in which the sulfur or nitrogen atom is coordinated to a metal center, depending on the nature of alkylating groups included as R'. We have trapped by protonation the proposed intermediate as the thioamide 12 [(CO)(5)W=[N-(CH(2))(4)-]CH(2)C(S)NHPh], which reveals the pathway of this reaction.

[Effect of Mexican propolis extracts from Apis mellifera on Candida albicans in vitro growth].

Propolis is a resinous substance collected by bees (Apis mellifera) from different trees and bushes. Due to its antifungal, antibacterial, antiviral and antiparasitic properties, it has continued to be very popular throughout the time showing variable activity depending on its geographical origin. In Mexico, information about this product is very limited.

Synthesis, characterization, and tautomerism of four novel copper(I) complexes from 3-hydroxy-3-(p-R-phenyl)-2-propenedithioic acids.

The paper describes the synthesis and structural characterization of four novel copper(I) complexes [CuL(PPh(3))(2)] (L = 3-hydroxy-3-(p-R-phenyl)-2-propenedithioate). In addition, a tautomeric equilibrium in solution was found and Hammett correlations with (13)C NMR parameters were studied. The structure of one complex was fully established by X-ray diffraction analysis.