Potential of acetates and related compounds in glacial acetic acid as a catalyst for aldol-type condensation reactions was examined. Reactions of cycloalkanones or selected heteroaromatics with aldehydes in presence of 10 mol% of various acetates in acetic acid afforded α,α'-bis(substituted-benzylidene)cycloalkanones and substituted-benzylidene-mackinazolinones, respectively, in good yields. Am...

Muramic acid is found in many peptide natural products containing oligo(poly)saccharide moieties. Taking into consideration that the Fmoc methodology is routinely used for solid-phase peptide synthesis, preparation of orthogonally protected muramic acid building blocks for total solid-phase synthesis of these natural products is of particular practical importance. Herein a simple and efficient ...

Chlamydiae are widespread Gram-negative pathogens of humans and animals. Salicylidene acylhydrazides, developed as inhibitors of type III secretion system (T3SS) in Yersinia spp., have an inhibitory effect on chlamydial infection. However, these inhibitors also have the capacity to chelate iron, and it is possible that their antichlamydial effects are caused by iron starvation. Therefore, we ha...

Some cyclic chalcone analogues [E-2-(X-benzylidene)-1-indanones, -tetralones, and -benzosuberones], on-plate UV light-catalyzed formation of new chromatographic spots, can be observed during thin-layer chromatography (TLC). Gas chromatographic (GC) analysis of selected derivatives indicates the formation of one new substance in each case. GC coupled with mass spectrometry and 1H NMR analysis of...

Specific deuterated reference compounds were prepared to probe the stereoselectivity of the reductive ring opening of carbohydrate-based benzylidene-type acetals. AlD(3) revealed a retentive stereoselectivity probably through the rare S(N)i (internal nucleophilic substitution) mechanism. An S(N)1-like mechanism occurs in the acid-promoted regioselective BD(3)·THF- or Et(3)SiD-reductive ring ope...

Oxidation of m- and p-substituted benzylidene fluorenes to antiaromatic dications was attempted by electrochemical and chemical means. Electrochemical oxidation to dications was successful for benzylidene fluorenes with p-methoxy, p-methyl, p-fluoro, and unsubstituted phenyl rings in the 3-position; attempts to oxidize the m-substituted derivatives via electrochemistry were unsuccessful. Chemic...

By the reaction of various amines with 3-chloropyridazines,several minaprine analogues were prepared.Most of them exhibited significant antidepressant activity.Compound 2a antagonizes reserpine action and neuroleptic-induced catalepsy in a dose-dependent manner. Keywords-disubstituted benzylidene pyridazine;3-amino pyridazine derivative,minaprine analogue;antidepressant activity Recently,it was...

The activation of heteromeric and homomeric nicotinic acetylcholine receptors was studied in Xenopus laevis oocytes to identify key structures of putative agonist molecules associated with the selective activation of homomeric alpha7 receptors. We observed that selectivity between alpha7 and alpha4beta2 was more readily obtained than selectivity between alpha7 and alpha3beta4. Based on structur...

A series of 2-(5-(6-Bromo-2-methyl-4-oxoquinazolin-3(4H)-yl)-4H-1,2,4-triazole-3-ylthio)-N-(substituted benzylidene) acetohydrazides (5a-5l) have been synthesized via condensation of 2-(5-(6-Bromo-2-methyl-4-oxaquinazolin-3 (4H)-yl)-4H-1,2,4-triazole-3-ylthio)acetohydrazide (4) with different aromatic aldehydes. Cycloaddition of thioglycolic acid with 5a-5l yielded 2-[5-(6-Bromo-2-methyl-4-oxoq...

The ring closing olefine metathesis in protic solvents using a new ruthenium benzylidene complex is described.