Microwave-assisted synthesis and transformations of sterically hindered 3-(5-tetrazolyl)pyridines

Tetrazoles and para‐Substituted Phenylazo‐Coupled Calix[4]arenes as Highly Sensitive Chromogenic Sensors for Ca2+

“…Accordingly, tetrazole groups can be readily synthesized by the reaction of nitrile with activated azide through the addition of either strong Lewis acids, [9] amine salts, [9b,9c] or dialkyltin oxides. [10,11] These reports prompted us to explore the syntheses of calix [4]arenes with bistetrazoles at the lower rim and para-substituted phenylazo moieties at the upper rim and their application in chromogenic sensing of metal ions, especially Ca 2+ .…”

Synthesis of sterically hindered 3-(azolyl)pyridines

“…These compounds together with previously described 3-(5-tetrazolyl)pyridines 27 and 3-(1,3,4-oxadiazol-2-yl)pyridines 27 could constitute a basis for a potential combinatorial library. This entire library containing more than 200 compounds was tested by the computer software PASS (Prediction of Activity Spectra for Substances).…”

“…Recently, we have reported the microwave-assisted synthesis of 3-(5-tetrazolyl)pyridines 2 and their fused polycyclic derivatives from sterically hindered nicotinonitriles 1. 27,28 The synthesis of 3-(1,3,4-oxadiazol-2-yl)pyridines 3 from the 3-(5-tetrazolyl)pyridines 2 was also described in one of these papers. 27 Herein, we wish to report the synthesis of 2,3,4-tri-and 2,3,4,5-tetrasubstituted pyridines bearing 1,2,4-oxadiazol-3-yl (4), imidazol-2-yl (5), and thiazol-2-yl (6) moieties at position 3 as well as methyl group at position 2.…”

“…27,28 The synthesis of 3-(1,3,4-oxadiazol-2-yl)pyridines 3 from the 3-(5-tetrazolyl)pyridines 2 was also described in one of these papers. 27 Herein, we wish to report the synthesis of 2,3,4-tri-and 2,3,4,5-tetrasubstituted pyridines bearing 1,2,4-oxadiazol-3-yl (4), imidazol-2-yl (5), and thiazol-2-yl (6) moieties at position 3 as well as methyl group at position 2. It should be noted that the 2,3-di-and 2,4,5-trisubstituted nicotinonitriles 1 had to be used as starting compounds common for the entire combinatorial library.…”

Synthesis and Cytotoxicity of Thiophene, Thieno[2,3-C]Pyrazole, Thieno[2,3-D]Pyrimidine and Pyridine Derivatives Derived from 2-Acetylfuran

“…They mainly involve intramolecular cyclization [4,5] multi component intermolecular cyclization [6] metal assisted coupling [7] microwave assisted coupling [8,9] or cycloaddition [10] azo electronic coupling [11] regioselective hetero Diels-Alder [12] and internal Mannich reaction [13]. They have been used in a wide hydrochloric acid.…”