An eco-friendly and practical method for the clean preparation of 5-amino-1,2,4-thiadiazoles was devel-oped.With WS_(2)as the semiconductor photocatalyst,both TEMPO and O_(2)(in air)as the redox catalysts,a variety of...An eco-friendly and practical method for the clean preparation of 5-amino-1,2,4-thiadiazoles was devel-oped.With WS_(2)as the semiconductor photocatalyst,both TEMPO and O_(2)(in air)as the redox catalysts,a variety of thiadiazoles were semi-heterogeneously formed in high to quantitative yields and could be easily collected by CPME extraction and rinsing.Furthermore,the catalytic system can be reusable for at least 5 reaction runs.展开更多
A rhodium-catalyzed denitrogenative carbonylation of 1,2,3-thiadiazole with alkynes to construct(benzo)thiochromenones is developed.Both terminal and internal alkynes were compatible in this[3+2+1]cycloaddition,afford...A rhodium-catalyzed denitrogenative carbonylation of 1,2,3-thiadiazole with alkynes to construct(benzo)thiochromenones is developed.Both terminal and internal alkynes were compatible in this[3+2+1]cycloaddition,affording a broad range of poly-substituted thiochromenones.Unsymmetrical alkyne substrates exhibited good regioselectivity.展开更多
Novel 1, 3, 4-thia(oxa)diazoles containing thienyl groups were synthesized. Analogous to the naturally-occurring compound, a-terthienyl, they can be photosensitized by ultraviolet light and showed phototoxicities agai...Novel 1, 3, 4-thia(oxa)diazoles containing thienyl groups were synthesized. Analogous to the naturally-occurring compound, a-terthienyl, they can be photosensitized by ultraviolet light and showed phototoxicities against the 2nd instar larvae of southern armyworm (Pseudaletia separata Walker), they also showed photocleavage action to pBR322 DNA.展开更多
The principle of using amplification reactions of iodine was employed in this paper to estimate the thiadiazole derivatives on basis of their reactions with iodine I chloroform, removal of the excess iodine and determ...The principle of using amplification reactions of iodine was employed in this paper to estimate the thiadiazole derivatives on basis of their reactions with iodine I chloroform, removal of the excess iodine and determination of the resulting iodide, after oxidation to iodate. The overall reaction gave an amplification of the iodide that is (12) times larger for the compounds: 2-amino-5-mercapto-1,3,4-thiadiazole (I);2,5-dimercapto-1,3,4-thiadiaole (II) and 2,5-diamino-1,3,4-thiadiazole (III) and (36) times for 2,5-dihydrazino-1,3,4-thiadiazole (IV) and (6) times for 5-mercapto-2[(3[5’-nitro-2-’furyl]·methylene)amino]-1,3,4-thiadiazole (V) and 5-mercapto-2[(3[5’-nitro-2-’furyl]-prop-2-enylidene)amino]-1,3,4-thiadiazole (VI). By titration, 1-mL of standard thiosulfate solution was found equivalent to 0.108 mg of (I);0.126 mg of (II), 0.16 mg of (III), 0.041 mg of (IV), 0.40 mg of (V) and 0.435 mg of (VI). Using the spectrophotometric detection for the amplification reaction gave high absorbance values at 605 nm for the blue starch-iodine complex. Beer’s law was obeyed up to 4.0 ppm for compounds (I and II);6.0 ppm for compounds (III, IV and VI) and 5.0 ppm for compound (V). The mechanism of the reactions was proposed and the analytical parameters were evaluated for both methods. The method was applied for synthetic samples of industrial importance. The recovery was comparable while the sensitivity and detection limits were better for the spectrophotometric detection.展开更多
A series of 3,6-disubstituted s-triazolo[3,4-b]-1,3,4-thiadiazoles have been synthesized,whose structures were determined by elemental and spectral analyses;all the new compounds showed significant antibacterial activ...A series of 3,6-disubstituted s-triazolo[3,4-b]-1,3,4-thiadiazoles have been synthesized,whose structures were determined by elemental and spectral analyses;all the new compounds showed significant antibacterial activity.展开更多
基金financial support from University of South China
文摘An eco-friendly and practical method for the clean preparation of 5-amino-1,2,4-thiadiazoles was devel-oped.With WS_(2)as the semiconductor photocatalyst,both TEMPO and O_(2)(in air)as the redox catalysts,a variety of thiadiazoles were semi-heterogeneously formed in high to quantitative yields and could be easily collected by CPME extraction and rinsing.Furthermore,the catalytic system can be reusable for at least 5 reaction runs.
基金We acknowledge the National Key R&D Program of China(No.2021YFA1501700)the NSFC(Nos.22131002,22161142019,81821004)the Tencent Foundation for financial support.
文摘A rhodium-catalyzed denitrogenative carbonylation of 1,2,3-thiadiazole with alkynes to construct(benzo)thiochromenones is developed.Both terminal and internal alkynes were compatible in this[3+2+1]cycloaddition,affording a broad range of poly-substituted thiochromenones.Unsymmetrical alkyne substrates exhibited good regioselectivity.
文摘Novel 1, 3, 4-thia(oxa)diazoles containing thienyl groups were synthesized. Analogous to the naturally-occurring compound, a-terthienyl, they can be photosensitized by ultraviolet light and showed phototoxicities against the 2nd instar larvae of southern armyworm (Pseudaletia separata Walker), they also showed photocleavage action to pBR322 DNA.
文摘The principle of using amplification reactions of iodine was employed in this paper to estimate the thiadiazole derivatives on basis of their reactions with iodine I chloroform, removal of the excess iodine and determination of the resulting iodide, after oxidation to iodate. The overall reaction gave an amplification of the iodide that is (12) times larger for the compounds: 2-amino-5-mercapto-1,3,4-thiadiazole (I);2,5-dimercapto-1,3,4-thiadiaole (II) and 2,5-diamino-1,3,4-thiadiazole (III) and (36) times for 2,5-dihydrazino-1,3,4-thiadiazole (IV) and (6) times for 5-mercapto-2[(3[5’-nitro-2-’furyl]·methylene)amino]-1,3,4-thiadiazole (V) and 5-mercapto-2[(3[5’-nitro-2-’furyl]-prop-2-enylidene)amino]-1,3,4-thiadiazole (VI). By titration, 1-mL of standard thiosulfate solution was found equivalent to 0.108 mg of (I);0.126 mg of (II), 0.16 mg of (III), 0.041 mg of (IV), 0.40 mg of (V) and 0.435 mg of (VI). Using the spectrophotometric detection for the amplification reaction gave high absorbance values at 605 nm for the blue starch-iodine complex. Beer’s law was obeyed up to 4.0 ppm for compounds (I and II);6.0 ppm for compounds (III, IV and VI) and 5.0 ppm for compound (V). The mechanism of the reactions was proposed and the analytical parameters were evaluated for both methods. The method was applied for synthetic samples of industrial importance. The recovery was comparable while the sensitivity and detection limits were better for the spectrophotometric detection.
文摘A series of 3,6-disubstituted s-triazolo[3,4-b]-1,3,4-thiadiazoles have been synthesized,whose structures were determined by elemental and spectral analyses;all the new compounds showed significant antibacterial activity.
