New Schiff bases from 2,5-bis-(butylsulfanyl)-2,3-dihydro-4H-pyran-2-carbaldehyde

Abstract

Novel densely functionalized Schiff bases have been synthesized by the reaction of 2,5-bis-(butylsulfanyl)-2,3dihydro-4H-pyran-2-carbaldehyde with primary amines and amino acids. Structure of the obtained compounds is confirmed using the data of elemental analysis, IR and NMR techniques, and chromatomassspectrometry.

2,5-Bis-(butylsulfanyl)-2,3-dihydro-4H-pyran-2-carbaldehyde in the synthesis of five-membered heterocycles

“…The reaction mixture was refluxed for 2-6 h. The solvent was removed under vacuum, and the residue was purified by column chromatography (SiO2, eluentchloroform). (6), 298 [M] + -SBu (6), 271 (7), 253 (37), 238 (9), 184 (7), 168 (5), 158 (53), 144 (6), 126 (26), 115 (9), 99 (14), 85 (20), 81 (24) (24), 356 (3), 312 (18), 267 (92), 238 (13), 228 (7), 211 (10), 200 (11), 184 (21), 172 (92), 155 (8), 144 (17), 126 (33), 112 (11), 99 (21), 85 (23), 71 (23), 57 (60), 55 (33), 41 (100). Calculated C19H31S2O4N (%): C, 56.86; H, 7.73; S, 15.96; N, 3.49.…”

“…For instance, some new Schiff bases were synthesized by the reaction of 2,5-bis(butylsulfanyl)-2,3-dihydro-4Hpyran-2-carbaldehyde with primary amines, as well as with amino acids and their esters. 14 The condensation of pyran 1 with 4-phenylthiosemicarbazide or thiosemicarbazide upon refluxing in EtOH afforded carbazones. 15 The synthesis of heterocycles from pyran 1 have not, so far, been implemented.…”