1072-71-5Relevant articles and documents
UV-induced transformations of matrix-isolated 1,3,4-thiadiazole-2-thiones
Rostkowska, Hanna,Lapinski, Leszek,Nowak, Maciej J.
, p. 56 - 66 (2010)
Monomers of 5-mercapto-1,3,4-thiadiazole-2-thione (bismuthiol) were studied using an experimental matrix-isolation technique as well as by carrying out theoretical quantum chemical calculations. The calculations, performed using the quadratic configuration interaction method with single and double excitations (QCISD)/6-31++G(d,p)//DFT(B3LYP)/ 6-311 ++G(2d,p), predict that the thione-thiol tautomer of bismuthiol should be significantly (by more than 19 kJ mol-1) more stable than other tautomeric forms. Accordingly, only the signatures of the thione-thiol tautomer were observed in the FT-IR spectrum of bismuthiol, recorded directly after deposition of an Ar matrix. UV (l> 320 nm) irradiation induced the conversion of the thione-thiol tautomer into the dithiol form. Analogous investigations were carried out for two related compounds: 5-methyl-1,3,4-thiadiazole-2-thione and 5-methylthio-1,3,4-thiadiazole-2-thione. For these two species, only the thione tautomeric forms were observed after deposition of Ar matrices. These tautomers were predicted (by QCISD calculations) to be more stable (by at least 19kJmol-1) than other tautomeric forms. Upon UV irradiation, the most stable thione forms of these compounds were transformed into the corresponding thiol tautomers. Direct observation of the thione! thiol phototautomeric processes provides a clear proof that intramolecular proton transfer reaction can occur in molecules, such as bismuthiol, in spite of the increased NH...S distance, in comparison to other phototautomerizing species studied so far. All the isomers of the studied compounds (substrates and products of the photoreactions) were identified by comparison of their IR spectra with the spectra calculated at the DFT(B3LYP)/6-311 ++G(2d,p) level of theory for possible isomeric structures. Copyright
Copper(I) Chloride π-Complexes with 2,5-Bis(Allylthio)-1,3,4-Thiadiazole: Synthesis and Structural Features
Slyvka, Yu. I.,Ardan,Mys’kiv
, p. 388 - 394 (2018)
Three new Cu(I) π-complexes with 2,5-bis(allylthio)-1,3,4-thiadizole (Bialtia) ([Cu3Cl3(Bialtia)2] (1), [Cu3Cl3(Bialtia)] (2), and [Cu2Cl2(Bialtia)] (3)) are obtained by the alternating current electrochemical synthesis and studied by single crystal X-ray diffraction. A distinctive feature of Bialtia is its ability to coordinate to Cu(I) atoms by nitrogen atoms of the thiadiazole core and two allyl groups. The formation of island inorganic {Cu3Cl3} moieties occurs in 1 through π coordination of two independent Bialtia molecules by three metal atoms. Due to the absence of one Bialtia molecule in 2, inorganic {–Cu3Cl3–} subunits join into infinite chains {[Cu3Cl3(Bialtia)]}n}. The structure of [Cu2Cl2(Bialtia)] (3) contains two Cu(I) atoms with different coordination environments: distorted tetrahedral and trigonal.
Synthesis of novel 2,5-bis(substituted thio)-1,3,4-thiadiazoles by acid catalyzed intermolecular cyclization reactions of substituted dithiocarbazates as a possible 2019-nCoV main protease inhibitor
Bhat, Muzzaffar A.,Butcher, Ray J,Jan, Misba,Jasinski, Jerry P.,Manzoor, Unjum,Shalla, Aabid H.
, (2022/01/03)
A convenient and facile synthesis of a privileged pharmaceutical scaffolds, 2,5-bis(substituted thio)-1,3,4-thiadiazoles is accomplished. The reaction of hydrazine hydrate with carbon disulfide and substituted alkyl/aryl chloride in basic medium yielded S-substituted alkyl/aryl dithiocarbazates in high yield. These dithiocarbazates on reaction with tetrafluoro acetic acid underwent a unique acid catalyzed intermolecular cyclization reaction to afford a novel 2,5-bis(substituted thio)-1,3,4-thiadiazoles. A simple procedure and high yields are the characteristic features of these reactions. These compounds are characterized on the basis of physico-chemical and spectral (FT-IR, ESI Mass, 1H, 13C and DEPT 135° 13C {1H} NMR) studies. Compound 2b crystallizes in orthorhombic system with point group P bca. Using the DFT/B3LYP/6–311 G (d,p) level of theory, HOMO-LUMO energy gap and molecular electrostatic potential (MEP) analyses were carried out. The HOMO-LUMO energy gap allowed the calculation of chemical hardness, chemical inertness, electronegativity and the electrophilicity index of the molecule, which depicted their potential kinetic stability and reactivity. The molecular docking studies of 2b-2e with 2019-nCoV main protease(7BRO) revealed binding free energies of (ΔGb) = -6.22, -5.38, -4.43 and -4.25 kcal mol?1 respectively. Docking study revealed that the aromatic congeners exhibit appreciable therapeutic efficiency to be used as 2019-nCoV main protease inhibitors.
Synthetic method of 2,5-dimercapto-1,3,4,-thiadiazole
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Paragraph 0028-0039, (2019/07/04)
The invention discloses a synthetic method of 2,5-dimercapto-1,3,4,-thiadiazole and mainly relates to the technical field of synthesis of fine chemicals. The synthetic method comprises the following steps: adding ethanol, a hydrazine hydrate, carbon disulfide and a solid base catalyst into a reaction vessel, stirring at a temperature of 20-100 DEG C to react for 1-10 hours, then cooling to room temperature, filtering, distilling filtrate under reduced pressure to remove a solvent to obtain a yellowish solid, and re-crystallizing with absolute ethyl alcohol to obtain a product DMTD. The synthetic method disclosed by the invention has the benefits that the solid base catalyst is adopted for catalysis, so that the problems that a traditional strong base catalyst corrodes equipment, and the product post-treatment is difficult are solved; the catalyst can be recycled and has the advantages of being mild in reaction conditions, low in production cost, low in equipment corrosion, easy in product separation, high in catalytic activity, low in environment pollution and the like; the synthetic method is a green synthetic technique.
