A straightforward and reliable method for the regioselective synthesis of steroidal 1,4-disubstituted triazoles and 1,5-disubstituted tetrazoles via copper(I)-catalyzed cycloadditions is reported. Heterocycle moieties were efficiently introduced onto the starting azide compound 3β-acetoxy-16β-azidomethylandrost-5-en-17β-ol through use of the "click" chemistry approach. The antiproliferative act...

We report here the first study of the protonated, neutral form of tetrazoles as anion binding functional groups. Our studies reveal them to be capable of binding anions with extremely high potency in polar solutions. In studying carboxylic acid-containing congeners, we find a remarkable discrepancy: a strictly analogous acid-containing host binds anions > or = 50,000-fold more weakly than the t...

A series of five novel bis-1,5-disubstituted-1H-tetrazoles (bis-1,5-DS-1H-T) were quickly prepared by a catalyst-free Ugi-azide repetitive process from easily accessible starting materials in excellent yields, either at room temperature (88%-95%) or using mild MW-heating conditions (80%-91%). These molecules may have a wide range of applications, such as chelating agents, organocatalysts and lu...

The synthesis and reactivity of tetrazol-5-yl-phosphorus ylides towards N-halosuccinimide/TMSN₃ reagent systems was explored, opening the way to new haloazidoalkenes bearing a tetrazol-5-yl substituent. These compounds were obtained as single isomers, except in one case. X-ray crystal structures were determined for three derivatives, establishing that the non-classical Wittig reaction leads to ...

A new series of novel heterocyclic compounds containing both tetrazoles and piperidine nuclei together, namely, 1-(1-aryl-1H-tetrazol-5-yl)-2-(piperidin-1-yl)ethanone (22-28), were synthesized by the treatment of the respective 2-chloro-1-(1-aryl-1H-tetrazol-5-yl)ethanone (15-21) with piperidine in acetonitrile for 6 h. A series of novel tetrazole substituted piperidine derivatives were synthes...