Synthesis and characterization of novel polyimides based on thiazole-containing diamine

A new kind of aromatic diamine monomer containing thiazole unit, 2-amino-5-（4-aminophenyl）-thiazole （AAPT）, was synthesized in three steps, starting from 4-nitroacetophenone. A novel thiazole-containing polyimide was prepared via the polycondensation of AAPT with 6FDA by one-step method. The resulting polyimide exhibits excellent solubility, film-forming capability and high thermal resistance.

Theoretical Study of Kinetics and Thermodynamics of Hetero Diels-Alder Reaction of Thiazole and Isothiazol with Thiophene-2,5-dione

DFT methods have been used to study the hetero Diels-Alder reaction of thiazole and isothiazole with thiophen-2,5-dione.The thermodynamic and kinetic parameters were calculated.The relative stabilities of the transition structures corresponding to the endo/exo stereoisomers have been rationalized on the basis of the secondary molecular orbital interactions.NBO analysis was carried out to calculate the synchronicity index.It was shown that all reactions are synchronous.A HOMO-LUMO energy gap shows both reactions are normal electron demand.

Synthesis and plant-growth regulatory activities of novel imine derivatives containing 1H-1,2,4-triazole and thiazole rings

Eleven new imine derivatives 6 containing 1H-1,2,4-triazole and thiazole rings were synthesized by the condensation of 5-((1H- 1,2,4-triazol-1-yl)methyl)-4-tert-butylthiazol-2-amine with various substituted benzaldehydes.The structures of the title compounds were characterized by ~1H NMR,MS and elemental analysis.The plant-growth regulatory activities of these compounds were evaluated.The primary bioassay results indicated that these target compounds exhibited promising plant-growth regulatory activities.

Synthesis,Crystal Structure and Biological Activity of 2-(1-(3-Bromo-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carbonyl)piperidin-4-yl)-N-isopropyl-1,3-thiazole-4-carboxamide

The title compound 2-（1-（3-bromo-1-（3-chloropyridin-2-yl）-1H-pyrazole-5-carbonyl）piperidin-4-yl）-N-isopropylthiazole-4-carboxamide（C21H22Br Cl N6O2 S,Mr = 536.04） has been synthesized,and its structure was characterized by IR spectra,1H-NMR,13C-NMR,EA,and single-crystal X-ray diffraction.The crystal of the title compound belongs to monoclinic system,space group P/c with a = 15.146（3）,b = 11.573（2）,c = 26.937（5） A,β = 103.64（3）°,V = 1839.0（6） A^3,Z = 4,Dc = 1.557 g/cm^3,μ（Mo Ka） = 0.71073 mm^-1,F（000） = 2192,R = 0.0601 and w R = 0.1392.There exist one intramolecular hydrogen bond at N–H···N and four intermolecular weak interactions at O（2）···H（1）,Cl（1）···H（12）,O（1）···Cl（1） and S（1）···O（2）.Bioassay results indicated that the title compound had good fungicidal and antiviral activities against tobacco mosaic virus.

Synthesis and Molecular Structure of 4-Chloromethyl-3-anilino-2-(4-methylbenzoylimido)thiazole

The title compound 2, 4-chloromethyl-3-anilino-2-（4-methyl-benzoylimido）thiazole, was prepared by the reaction of 1-p-methylbenzoyl-3-phenylaminothiourea 1 with 1,3-dichloro- acetone. The crystal is of monoclinic, space group P21/c, with a = 8.1712（15）, b = 10.998（2）, c = 19.134（4）A, β= 94.610（5）°, C18H16ClN3OS, Mr = 357.85, Z = 4, V = 1714.0（6）A^3, De= 1.387 g/cm^3, μ（MoKa） = 0.354 mm^-1, F（000） = 744, the final R = 0.0518 and wR = 0.1167 for 3189 observed reflections （I〉 2σ（I）. Its formation mechanism was proposed.

Thiazolo[5,4-d]thiazole-based covalent organic framework microspheres for blue light photocatalytic selective oxidation of amines with O2

Covalent organic frameworks(COFs)with photoactive units have attracted significant interest in visible light photocatalysis and can present a metal‐free scenario for activating O_(2).As a typical photoactive unit,thiazolo[5,4‐d]thiazole(TzTz)has rarely been added to COFs.However,circumventing the low reversibility of TzTz,it could be embedded into the building blocks beforehand,along with other bonds likeβ‐ketoenamine in forming COFs.TzTz was embedded into 1,1′‐biphenyl‐4,4′‐diamine(BD)using this approach to produce 4,4′‐(TzTz‐2,5‐diyl)dianiline(DTz).Under organobase‐modulated solvothermal conditions,combining 1,3,5‐triformylphloroglucinol(Tp)with BD and DTz resulted in the production ofβ‐ketoenamine‐linked TpBD‐COF and TpDTz‐COF.Both TpDTz‐COF and TpBD‐COF are microspheres.TpDTz‐COF possessed more adequate separation and charge migration than TpBD‐COF.This resulted in superior performance for the blue light photocatalytic selective oxidation of benzylamine with O_(2).Furthermore,with O_(2) as the main oxidant,a wealth of benzylamines could be converted into imines over TpDTz‐COF.Mechanistic investigations substantiate that oxidation of benzylamines obeys an electron transfer pathway,in which superoxide anion(O_(2)•–)is the crucial reactive oxygen species.This study highlights the superiority of TzTz‐embedded COFs in developing effective photocatalytic systems for organic transformations.

Design, Synthesis and in vitro Evaluation of Thiazole Derivatives of Ibuprofen as Cyclooxygenase-2 Inhibitors

A series of thiazole derivatives of ibuprofen, as cyclooxygenase-2 Inhibitors, were designed, synthesized and in vitro evaluated.

Synthesis of Some More New Sulfur-containing Heterocyclic Compounds as Biocidal Agents- Part II： Synthetic of 2-thioxo thiazole/thia diazole and 3-thioxo-1,3,4-triazole Derivatives

Some new 2-thioxo thiazole, 2-thioxo 1,3,4- thiadiazole and 3-thioxo-1,3,4-triazole derivatives （3-17） have been synthesized through ring closure reactions ofdithioic formic acid hydrazones 2 with functional reagents in different medium. Former structures of the products have been established by the help of elemental and spectral analysis. Most of the obtained targets showed a moderate activity towards some microbes in comparison with two antibiotics Pipercillin and Mycostatine.

Synthesis of Novel Ferrocenyl-containing Thiazole Derivatives

Novel ferrocenyl-containing thiazole derivatives have been synthesized from 2-amino-4-ferrocenyl-5-（1H-1, 2, 4-triazole-l-yl）thiazole and acyl chloride. And their structures were determined by 1H NMR and elemental analysis.

Synthesis, Crystal Structure and Fungicidal Activity of Ethyl 2-(3-(4-Fluorobenzamido)phenyl)-4-((4-fluorobenzoyl)oxy)thiazole-5-carboxylate

The target compound, ethyl 2-（3-（4-fluorobenzamido）phenyl）-4-（（4-fluorobenzoyl）oxy） thiazole-5-carboxylate, was synthesized by four-step procedures including N-protection, thionation, cyclization and acylation. Its structure was characterized by 1 H NMR, 13C NMR, HRMS and single-crystal X-ray diffraction. The target compound crystallizes as monoclinic crystal system, space group C2/c with a = 9.6097（19）, b = 14.246（3）, c = 33.070（7） ?, V = 4515.1（16） ?3, Z = 8, Dc = 1.496 Mg/m3, F（000） = 2096 and μ = 0.203 mm-1. There are 21864 reflections measured（4.94≤2θ≤55.96°）, of which 5357 were unique（Rint = 0.1418） and used in all calculations. The final R = 0.0581（I > 2σ（I）） and wR = 0.1453（reflections）. The target compound showed over 50% of growth inhibition against Physalospora piricola, Rhizoctonia cerealis and Sclerotinia sclerotiorum.

A Thiazole-Based Polymer Donor for Efficient Organic Solar Cells

The development of new materials plays a critical role in improving the efficiency of organic solar cells(OSCs).At present,the relatively high-lying highest occupied molecular orbital(HOMO)level of the high-efficiency polymer donor is regarded as one of the main reasons for the low open-circuit voltage(V_(OC)).In this work,we introduced the strong electron-withdrawing thiazole unit into the construction of a polymer donor.We designed and prepared an alternating donor-acceptor material,namely PSZ,by copolymerizing 4-methyl thiazole with an electron-donating benzodithiophene unit and studied its application in high-efficiency OSCs.The optical and electrical properties of the new material were characterized by UV-Vis absorption spectroscopy and electrochemical cyclic voltammetry.Results show that PSZ is a typical wide-bandgap material with a high optical bandgap of 2.0 eV and a deep HOMO level of-5.70 eV.When a non-fullerene BTP-eC9 was selected as the acceptor material,V_(OC) reached 0.88 V in the resulting device,and the corresponding power conversion efficiency(PCE)was8.15%.In addition,when PSZ was added as the third component to the binary photoactive combination with PBDB-TF as the donor and BTP-eC9 as the acceptor,V_(OC) of the cell device could be increased,thereby obtaining a high PCE of 17.4%.These results indicated that introducing thiazole units into polymer donors can remarkably reduce the HOMO levels and improve V_(OC) and PCE in OSCs.

Preparation of α-Bromoketones and Thiazoles from Ketones with NBS and Thioamides in Ionic Liquids

Ketones smoothly reacted with NBS in the presence of a catalytic amount of ptoluenesulfonic acid to give α-bromoketones in good yields in typical ionic liquids, such as [bmim]PF6 and [bmpy]Tf2N, and the ionic liquids could be repeatedly used for the same reaction after the extraction of the α-bromoketones. Then, the one-pot conversion of ketones into thiazoles by the treatment with NBS, and subsequently with thioamides could be also carried out in [bmim]PF6 and [bmpy]Tf2N, respectively Thus, [bmim]PF6 and [bmpy]Tf2N could be used as recyclable reaction media for the preparation α-bromoketones and thiazoles from ketones.

A Thiazole Analogue Exhibits an Anti-Proliferative Effect in Different Human Carcinoma Cell Lines and Its Mechanism Based on Molecular Modeling

Purpose: Aim of this study is to assess the anti-proliferative effect of the thiazole analogue (5-acetyl-4-methyl-2-(3-pyridyl) thiazole) with different human carcinoma cell lines and to postulate its possible mechanism of action using molecular modeling. Methods: Three different human carcinoma cell lines were used namely hepatocyte carcinoma (HEPG2), breast adenocarcinoma (MCF7) and colon cancer (HCT116). Molecular docking simulations for tested thiazole analogue and its virtual analogues against the cytochrome P-450 2A6 enzyme and mutated SOD were performed. Results: Cell lines cytotoxicity revealed that the tested thiazole analogue exerts a significant anti-proliferative activity in all the used human carcinoma cell lines with a pronounced anti-proliferative effect in liver carcinoma cell line HEPG2 (IC50 = 23.8 μg/ml) whereas the anti-proliferative effect in colon carcinoma and breast cancer cell lines was poor with IC50 = 50 μg/ml and IC50 > 50 μg/ml respectively. The postulated mechanism of action revealed the high affinity to inhibit SOD and CYP2A6 enzymes in the liver. Conclusion: The thiazole analogue (5-acetyl-4-methyl-2-(3-pyridyl)thiazole) is a potential liver specific anticancer agent capable of interfering with both apoptotic signaling pathway and the free radical processing in liver which leads to more studies on liver cancer from different perspective rather than the apoptotic signaling pathway.

Enhancing the Efficiency and Durability of Perovskite Solar Cells by Donor-Acceptor Covalent Organic Framework with Thiazolo[5,4-d]thiazole Unit

Donor-Acceptor(D-A)alignment is considered a productive strategy to improve the charge separation efficiency of covalent organic frameworks(COFs)and enhance the charge-transfer yield(CTY)of COFs.Moreover,organic molecules containing heteroatoms can produce coordination interaction with PbI2 of perovskite precursor to affect the crystallization process,thereby impeding the decomposition and improving the stability of perovskite materials.Herein,a thiazolo[5,4-d]thiazole(TZ)-based D-A type COF_(TPDA-TZDA) was designed and synthesized from N,N,N′,N′-tetrakis(4-aminophenyl)-1,4-benzenediamine(TPDA)and 4,4′-(thiazolo[5,4-d]thiazole-2,5-diyl)dibenzaldehyde(TZDA).Upon incorporation into the FAPbI3 layer,COF_(TPDA-TZDA) not only restrained the perovskite defects and enhanced the grain size of perovskite films through the coordination effect of the N atoms of TZDA but also ameliorated the charge transport within the perovskite film,which was the benefit of the D-A structure of COF_(TPDA-TZDA).As a result,incorporation of COF_(TPDA-TZDA) into the perovskite solar cells(PSCs)led to a remarkable power conversion efficiency(PCE)of up to 23.51%.Furthermore,even after being stored in high relative humidity(RH≈60%)for 480 h,these PSCs maintained over 90.55%of their original PCE.This work sets the foundation for the development of highly efficient and stable PSCs by utilizing TZ-based D-A type COFs.

Synthesis, Photophysical Properties and TD-DFT Calculation of Fluorescent Dyes Based on Pyrenylthiazoles

Pyrene is one of significant fluorescent material and its fluorescence properties are excellent.It has been widely used for such as OLEDs,DSCs,LMOGs and so on[1-5].What＇s more,pyrene has been successfully applied to signaling the presence of metal ions,nucleic acids,proteins and so on[6-9].Thus,the development of the fluorescent dyes based on pyrene has been a research focus[10-12].However,the synthesis of many pyrene derivatives needed the high-cost coupling reaction such as Heck reaction and Suzuki reaction[1-3,10-12].

Benzobisthiazole Polymer with Resonance-assisted Hydrogen Bonds for High-performance Transistor and Solar Cell Applications

Benzobisthiazole polymer with resonance-assisted hydrogen bonds(RAHBs)has been synthesized for both organic field-effect transistor and polymer solar cell applications.The properties of the hydrogen bonded polymer are compared with the reference polymer without RAHBs.Single-crystal X-ray diffraction analyses of the building block reveal that the RAHB interactions are formed between the carbamate hydrogen and imine nitrogen of the thiazoles.The hydrogen donor and acceptor are connected byπ-conjugated molecular framework and the hydrogen-bridged quasi aromatic rings lock the conformation of the building block.The building block adopted a layered sandwich packing in crystal instead of slipped herringbone stacking which was often found in the crystal of benzobisthiazole derivatives.The polymer PCBTZ-TT with RAHBs showed deeper HOMO/LUMO energy level(about 0.2 eV)than reference polymer.The PCBTZ-TT demonstrated the hole mobility of0.96 cm^(2)·V^(-1)·s^(-1) in field-effect transistor devices and achieved power conversion efficiency of 13.6%in solar cell devices with Y6 as acceptor without any additive.

Synthesis and Biological Evaluation of Quinazolonethiazoles as New Potential Conquerors towards Pseudomonas Aeruginosa

Novel quinazolonthiazoles were designed and synthesized as new potential antimicrobial agents by facile multi-step procedure from o-aminobenzoic acids and 2-acetylthiazole.A series of biological evaluation showed that compound 7d was the most effective quinazolonethiazole with superior activity to reference drugs chloramphenicol and norfloxacin.This active molecule displayed unob-vious bacterial resistance against P.aeruginosa,the low toxicity to normal hepatocytes,suitable pharmacokinetics and drug-likeness.The preliminary biological interaction suggested that quinazolonethiazole 7d might induce bacterial death by disturbing the membrane permeability,whilst preventing bacteria from growth by integrating into DNA and binding with topoisomerase IV.These findings provided significant background for the further development of quinazolonethiazoles as new potential drugs in combating drug-resistant pathogens.

Convenient synthesis of 2-arylbenzothiazoles and 2-arylnaphthothiazoles

Thiazoles including five 2-arylbenzothiazoles and two 2-arylnaphthothiazoles were synthesized using a simple synthetic strategy in this work.2-Arylbenzothiazoles and 2-arylnaphthothiazoles can be prepared by the reaction of methylaromatics with aniline or naphthylamine in the presence of elemental sulfur,respectively.All the seven thiazoles were characterized by the melting point measurement,FTIR,~1H NMR,^（13）C NMR and GC-MS analysis.