We investigated the effect of fifteen 1,5-disubstituted imidazoles (1,5-dis) on juvenile hormone III (JH III) and methyl farnesoate (MF) biosynthesis by the corpora allata (CA) of the mosquito Aedes aegypti in vitro. Four compounds (TH-35, TH-83, TH-62 and TH-28) significantly decreased JH biosynthesis in the CA dissected from 3-day old sugar-fed females. The decrease of JH synthesis was not al...

Synthetic procedures have been developed to provide 2,3-disubstituted-3,4-dihydro-1(2H)-isoquinolinones 6, 10, and 15 from (1R,2S)-ephedrine, (1R,2R)-pseudoephedrine, and L-phenylalanine. Birch reduction of 6 and 10 gave enantiomerically related lactam enolates that were alkylated with methyl iodide, allyl bromide, benzyl bromide, p-benzyloxybenzyl bromide, and p-methoxybenzyl bromide to give 7...

Tandem reactions involving Rh-catalyzed intermolecular hydroacylations of alkynes with salicylaldehydes followed by intramolecular oxo-Michael additions are described for the diastereoselective synthesis of 2,3-disubstituted chroman-4-ones. The tandem hydroacylation/oxo-Michael additions occur to form 2,3-disubstituted chroman-4-ones in high yields from a range of 1,2-disubstituted acetylenes a...

Divergent syntheses of indolizines and 2,4-disubstituted pyrroles by the silver-catalyzed cyclization of 2-pyridyl alkynyl carbinols with isocyanides are reported. These methods provide an effective route to highly functionalized indolizines and 2,4-disubstituted pyrroles in good to excellent yields. The 2,4-disubstituted pyrroles are synthesized by an unprecedented regioselective [3+2] cycload...

The dominant alkaloids previously identified in skin extracts of Amazonian dendrobatid frogs of the genus Ameerega are histrionicotoxins and 2,5-disubstituted decahydroquinolines. Analysis of alkaloids in skin extracts of Ameerega picta from Bolivia revealed that the alkaloid 257A, previously reported as a 2,5-disubstituted decahydroquinoline, is an N-methyl-2,5-disubstituted decahydroquinoline...

Accepted on 26 th December 2016, Published online on 27 th January 2017 _____________________________________________________________________________ ABSTRACT During the present investigation, a new series of 3,6-disubstituted[1,2,4]triazolo[3,4-b][1,3,4]thiadiazole derivatives (3) were synthesized by refluxing a mixture of 3-substituted-4-amino-5-mercapto-1,2,4triazoles with substituted anilin...

Mixtures of 2,4- and 2,5-disubstituted zirconacyclopentadienes were obtained by the reductive dimerisation of terminal alkynes using the Cp2ZrCl2/lanthanum system. Reactions of dihalophosphines with these mixtures afforded selectively the corresponding 2,4-disubstituted phospholes and 1,4-disubstituted butadienes. A new series of phospholes was characterized by multi-nuclear NMR spectroscopy an...