Thiazoles and thiazolyl-pyrazole derivatives have been efficiently synthesized under neat reaction conditions in excellent yields. Condensation of 3-(2-bromoacetyl)-4-hydroxy-6-methyl-2H-pyran-2-one (1), thiosemicarbazide (2) and various carbonyl compounds (3 & 5) gave corresponding thiazole (4) and thiazolylpyrazole derivatives (6) in excellent yields by using Hantzsch-Thiazole synthesis. The ...

A reinvestigation of a chiral phosphoric-acid-catalyzed four-component Hantzsch enantioselective synthesis polyhydroquinolines reported in 2009 is presented. In our hands, when the reaction was performed with fidelity to original report using enantiopure phosphoric acid catalyst, no enantioselectivity observed. Unlike report, results are backed by baseline separation enantiomers HPLC analyses o...

Abstract: Thiazole or 1,3-thiazole is a distinct heterocyclic compound which incorporates sulphur and nitrogen atoms. It vital framework present in numerous pharmacologically active compounds, be it of natural origin synthetic nature. Many thiazoles having antitumor antiviral activities, originate from microbes marine organisms. A variety drugs, thiazole group, like antimicrobial sulfathiazole,...

The polymer supported hypochlorite ion is a facile selective oxidizing agent for the oxidation of various alcohols to aldehydes and ketones. Similarly is successfully oxidizes various Hantzsch type 1,4- dihydropyridines to corresponding pyridines.

A continuous-flow asymmetric organocatalytic photocyclization-transfer hydrogenation cascade reaction has been developed. The new protocol allows the synthesis of tetrahydroquinolines from readily available 2-aminochalcones using a combination of photochemistry and asymmetric Brønsted acid catalysis. The photocylization and subsequent reduction was performed with catalytic amount of chiral BINO...

A novel and green approach for efficient and rapid synthesis of biologically active polyhydroquinoline derivatives via unsymmetric Hantzsch reaction using nanorods Vanadatesulfuric acid (VSA NRs) as a new and recyclable catalyst under solvent-free conditions was reported. The catalyst was characterized by FT-IR, XRD, XRF and TEM analysis. The present method offers several advantages such as sim...

Hantzsch esters (1,4-dihydropyridine dicarboxylates) have become, in this century, very versatile reagents for enantioselective organic transformations. They can act as hydride transfer agents to reduce, regioselectively, a variety of multiple bonds, e.g., C=C and C=N, under mild reaction conditions. are excellent the dearomatization heteroaromatic substances, participate readily cascade proces...

by four technologists), the coefficient of variation was 5.5% (93.6 mg/dl ± 5.0 SD). We have used the method successfully, without technical difficulties. The advantages: the method is colorimetnc and requires no special equipment; although manual, it is rapid, and 30 to 40 specimens can be processed in 3 h; it is reproducible and the results compare well to those obtained by other Hantzsch con...