TY - JOUR

T1 - Synthesis of Thiadiazoles Based on Phloroglucinol Derivatives and Their Glycosylation.

AU - Сандрюхина, М.В.

AU - Певзнер, Леонид

AU - Петров, М.Л.

AU - Степаков, Александр Владимирович

PY - 2024/4/1

Y1 - 2024/4/1

N2 - Abstract: 4-(2,4,6-Trimethoxyphenyl)-1,2,3-thiadiazole was synthesized by the Hurd–Mori reaction starting from 2,4,6-trimethoxyacetophenone. Demethylation of 4-(2,4,6-trimethoxyphenyl)-1,2,3-thiadiazole in presence of aluminum trichloride proceeds chemoselectively to give 4-(2-hydroxy-4,6-dimethoxyphenyl)-1,2,3-thiadiazole. The latter is glycosylated with 1-α-bromo-2,3,4,6-tetra-O-acetyl-D-glucopyranose and 1-α-bromo-2,3,4,6-tetra-O-acetyl-D-galactopyranose under the conditions of the phase transfer variant of the Kennigs–Knorr reaction to form corresponding α-glycosides. Nitration of 4-(2-hydroxy-4,6-dimethoxyphenyl)-1,2,3-thiadiazole with nitric acid gives 4-(2-hydroxy-3-nitro-4,6-dimethoxyhenyl)-1,2,3-thiadiazole, which, under the above-mentioned conditions, is glycosylated with 1-α-bromo-2,3,4-tri-O-acetyl-D-xylopyranose to corresponding β-glycoside. Under the condition of Fries rearrangement, 3,5-dimethoxyphenyl acetate forms two products, 2-hydroxy-4,6-dimethoxyacetophenone (xantoxylin) and 1,1′-(2-dihydroxy-4,6-dimethoxy-1,3-phenylene)bis(ethan-1-one). Formation of xantoxylin carbethoxyhydrazone proceeds difficultly. When heated with thionyl chloride it converts to labile 4-(2-hydroxy-3,5-dichloro-4,6-dimethoxyphenyl-1,2,4-thiadiazole. 1,1′-(2-Dihydroxy-4,6-dimethoxy-1,3-phenylene)bis(ethan-1-one) under the conditions of the Hurd–Mori reaction gives 3,5-dimethoxy-2,6-bis(1,2,3-thiadiazol-4-yl)phenol.

AB - Abstract: 4-(2,4,6-Trimethoxyphenyl)-1,2,3-thiadiazole was synthesized by the Hurd–Mori reaction starting from 2,4,6-trimethoxyacetophenone. Demethylation of 4-(2,4,6-trimethoxyphenyl)-1,2,3-thiadiazole in presence of aluminum trichloride proceeds chemoselectively to give 4-(2-hydroxy-4,6-dimethoxyphenyl)-1,2,3-thiadiazole. The latter is glycosylated with 1-α-bromo-2,3,4,6-tetra-O-acetyl-D-glucopyranose and 1-α-bromo-2,3,4,6-tetra-O-acetyl-D-galactopyranose under the conditions of the phase transfer variant of the Kennigs–Knorr reaction to form corresponding α-glycosides. Nitration of 4-(2-hydroxy-4,6-dimethoxyphenyl)-1,2,3-thiadiazole with nitric acid gives 4-(2-hydroxy-3-nitro-4,6-dimethoxyhenyl)-1,2,3-thiadiazole, which, under the above-mentioned conditions, is glycosylated with 1-α-bromo-2,3,4-tri-O-acetyl-D-xylopyranose to corresponding β-glycoside. Under the condition of Fries rearrangement, 3,5-dimethoxyphenyl acetate forms two products, 2-hydroxy-4,6-dimethoxyacetophenone (xantoxylin) and 1,1′-(2-dihydroxy-4,6-dimethoxy-1,3-phenylene)bis(ethan-1-one). Formation of xantoxylin carbethoxyhydrazone proceeds difficultly. When heated with thionyl chloride it converts to labile 4-(2-hydroxy-3,5-dichloro-4,6-dimethoxyphenyl-1,2,4-thiadiazole. 1,1′-(2-Dihydroxy-4,6-dimethoxy-1,3-phenylene)bis(ethan-1-one) under the conditions of the Hurd–Mori reaction gives 3,5-dimethoxy-2,6-bis(1,2,3-thiadiazol-4-yl)phenol.

KW - 2,4,6-trimethoxyacetophenone

KW - Fries rearrangement

KW - Hurd–Mori reaction

KW - glycosylation

KW - thiadiazoles

UR - https://www.mendeley.com/catalogue/e57cf5e0-1fc4-3712-b483-536768cbee9c/

U2 - 10.1134/S1070363224040091

DO - 10.1134/S1070363224040091

M3 - Article

VL - 94

SP - 824

EP - 834

JO - Russian Journal of General Chemistry

JF - Russian Journal of General Chemistry

SN - 1070-3632

IS - 4

ER -