Synthesis and antitumor activity of novel pyridazinone derivatives containing 1,3,4-thiadiazole moiety

Abstract

A series of novel pyridazinone derivatives containing the 1,3,4-thiadiazole moiety were synthesized and characterized by ¹H NMR, 13C NMR, spectroscopies HRMS and IR. Among them, the structure of compound 5c (2-(Tert-butyl)?4-chloro-5-((5-((2-ethylphenyl)amino)?1,3,4-thiadiazol-2-yl)thio)pyridazin-3(2H)-One) was unambiguously confirmed via single crystal X-ray diffraction analysis. The inhibitory activity of all the target compounds against MGC-803 and Bcap-37 was determined by MTT assay, with doxorubicin (the inhibition rates were 95.5?±?0.4% and 95.7?±?1.0% respectively) as a control. The preliminary results showed that the inhibitory activity of compound 5n (2-(Tert-butyl)?4-chloro-5-((5-((3-fluorophenyl)amino)?1,3,4-thiadiazol-2-yl)thio)pyridazin-3(2H)-One) was superior to the others. The inhibition rates of MGC-803 and Bcap-37 cells were 86.3?±?2.2% and 92.3?±?0.6% at a concentration of 10?μmol/L, respectively. The preliminary structure-activity relationship showed that when the 2-position of the benzene ring was substituted by a methyl group, such as compound 5j (2-(Tert-butyl)?4-chloro-5-((5-((2,3-dimethylphenyl)amino)?1,3,4-thiadiazol-2-yl)thio)pyridazin-3(2H)-One), it exhibited good anticancer activity on MGC-803 cells. Besides, introducing fluorine, chlorine, or trifluoromethyl group onto the benzene ring, such as compound 5?m (2-(Tert-butyl)?4-chloro-5-((5-((4-(trifluoromethoxy)phenyl)amino)?1,3,4-thiadiazol-2-yl)thio)pyridazin-3(2H)-One), displayed good anticancer activity on MGC-803 and Bcap-37 cells.     

2-取代硫醚-5-脱氢松香基-1,3,4-恶二唑/噻二唑类化合物的合成及生物活性

以脱氢松香酸为原料,经酯化、肼解、关环和亲核取代反应得到了2-取代硫醚-5-脱氢松香基-1,3,4-恶二唑和2-取代硫醚-5-脱氢松香基-1,3,4-噻二唑类化合物。通过IR、MS、1H NMR和元素分析对产物进行了表征。初步生物活性检测结果表明,所有目标化合物都表现出一定的除草活性。     

1,3,4-均三唑并[2,1-b]-1,3,4-噻二唑衍生物的合成及生物活性

以5-对甲苯基-1-氨基-2-巯基-1,3,4-均三唑和取代苯氧乙酰异硫氰酸酯为原料, 合成了10个未见文献报道的5-对甲苯基-2-取代苯氧乙酰氨基均三唑并[2,1-b]-1,3,4-噻二唑类化合物, 通过元素分析, 1H NMR, IR和MS确定化合物的结构, 初步生物活性测试表明目标化合物具有较好的除草活性.     

1,3,4-噻二唑基1,2,4-三唑啉酮类化合物的合成及除草活性

以2-甲基-5-氨基-1,3,4-噻二唑和芳香醛为原料,设计合成了一系列新型1,2,4-三唑啉酮类化合物。通过1H MR、MS和元素分析确证了其结构。生物活性测试结果表明,在100μg·m L-1浓度下,该类化合物具有较好的除草活性,其中化合物4c和4d对油菜和稗草的抑制率达到了80%。     

Synthesis of 3,6-bisubstituted phenyl-bi-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazole derivatives

2,5-Bihydrazino-1,3,4-thiadiazole (2) was synthesized by condensation of 2,5-bimercapto-1,3,4-thiadiazole (1) with hydrazine hydrate, and compound 2 reacted with acyl chloride to give 2,5-biacylhydrazino-1,3,4-thiadiazole derivatives (3a–3e). Ring closure of compounds 3a–3e was achieved with POCl3 as the cyclization agent giving 3,6-bisubstituted phenyl-bi-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazole derivatives (4a–4e), respectively. The novel compounds were identified by elemental analysis, and by infrared (IR), 1H-nuclear magnetic resonance (NMR), and mass (MS) spectrometry. The mechanism of the cyclization is also discussed. __________ Translated from Organic Chemistry, 2006, 26(12): 1720–1722 [译自: 有机化学]     

Synthesis,characterization, computational studies and biological activities of Co(II), Ni(II) and Cu(II) complexes of 2-Amino-1,3,4-thiadiazole derivatives

Abstract

Co(II), Ni(II), and Cu(II) complexes of 2-Amino-5-ethyl-1,3,4-thiadiazole (AET) and 2-Amino-5-(ethylthio)-1,3,4-thiadiazole (AEST) have been synthesized and characterized based on elemental analysis, magnetic susceptibility, infrared (4000–400 cm^?1), mass spectrometry (ESI and MALDI), UV–Vis (200–1100 nm) and thermal analysis (TGA/DTA). Molar conductance measurements proved that [M(L)₂(H₂O)₂]Cl₂·H₂O are electrolytic complexes where M represents Co, Ni, and Cu divalent metal ions. The geometrical isomerism of [M(L)₂(H₂O)₂]²⁺ ions were investigated by DFT-B3LYP calculations incorporated in Gaussian09 package; it favored the all trans isomers due to having the lowest energy points on the potential energy surface. The outcome of DFT-B3LYP quantum mechanical calculations using 6-31G(d) basis set favor six-coordinate sites via a bidentate ligand through exo amino and adjacent endo thiadiazole nitrogen (N₃) donors. These results were consistent with magnetic measurements combined with infrared and UV–Vis spectral interpretations. The predicted metal–ligand binding energies from B3LYP/6-31G(d) calculations follow the trend Cu²⁺>Ni²⁺>Co²⁺, in agreement with the Irving–Williams series. Both AET and AEST ligands and the synthesized complexes were screened for their antibacterial activity and the outcome was high antimicrobial activity of the complexes compared to the free ligands against one or more microbial species and in some cases (copper complexes) higher activity than standard drugs.     

Synthesis and Antibacterial Activity of Substituted Thiosemicarbazides and of 1,3,4-Thiadiazole or 1,2,4-Triazole Derivatives

The synthesized series of new thiosemicarbazide derivatives ( 1 , 6–10 ) in reactions with carbon disulphide produced, according to the reaction conditions, the dithioacids ( 4 , 30 ) or the 5-substituted 1,3,4-thiadiazolo-2-thiol derivatives ( 2 , 27 ). The dithioacids were cyclized, in the reaction with hydrazine, into the 4-ami-no-1,2,4-triazolo-2-thiol derivatives ( 5 , 31 ). One of these compounds ( 31 ) was transformed into the 1,2,4-triazolo-1,3,4-thiadiazine derivative ( 33 ). The compo-unds 6–9 were also exposed to the condensation with aldehydes. 4-phenylpipera-zinocarbothiohydrazide ( 6 ) was exposed to the action of isothiocyanates, which gave the compounds 16–20 , and these cyclized to the 1,3,4-thiadiazoloamino derivatives ( 21–23 ).

The susceptibility of aerobic and anaerobic bacteria to some of the new derivatives were tested. The anaerobes were the most susceptible at concentrations in ranges less than 6.2 to 100 μg/mL to derivative: 9 (64% were susceptible), 1 , 13 (for 60%), and 7 (for 56%).     

芳醛-[5-(3,4,5-三甲氧基苯基)-1,3,4-噻二唑-2-巯基]-乙酰腙衍生物的合成及生物活性研究

采用活性基团拼接法, 以2-巯基-5-(3,4,5-三甲氧基苯基)-1,3,4-噻二唑为原料, 经硫醚化、肼解、腙化反应合成了8个芳醛-[5-(3,4,5-三甲氧基苯基)-1,3,4-噻二唑-2-巯基]-乙酰腙衍生物, 并经过元素分析, IR, ¹H NMR, ¹³C NMR对其结构进行了确认. 初步生物活性测试表明, 部分化合物具有一定的抑菌生物活性.     

Synthesis of 4,5-Dihydro-1,3,4-thiadiazole-2-carboxamide and 2-Carbamoyl-4,5-dihydro-1,3,4-thiadiazole 1-Oxide Derivatives Based on Hydrazones of Oxamic Acid Thiohydrazides

We have developed a method for obtaining derivatives of 4,5-dihydro-1,3,4-thiadiazole-2-carboxamide by acylation of hydrazones of oxamic acid thiohydrazides. Oxidation of the dihydrothiadiazole ring of the indicated products by hydrogen peroxide leads to formation of 2-carbamoyl-4,5-dihydro-1,3,4-thiadiazole 1-oxides.     

Salts of 2,5-dimercapto-1,3,4-thiadiazole

Reaction of 2,5-dimercapto-1,3,4-thiadiazole with ammonia or pyridine gives monoammonium or monopyridinium slats, and the reaction with hydrazine hydrate gives both mono- and dihydrazine salts, which was confirmed by alkylation of the salts obtained. Difference in the chemical shifts of the SCH₂R groups was found in the¹H NMR spectra of the mono- and dialkyl-substituted 2,5-dimercapto-1,3,4-thiadiazoles.Institute of Chemistry, Vilnius LT-2600, LithuaniaTranslated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 682–687, May, 2000.     

Chemoselective one-pot synthesis of 2-phenylamino-5-alkylthio-1,3,4-thiadiazole derivatives from phenylthiosemicarbazide and CS2

A novel and fairly efficient chemoselective one-pot method has been developed for the synthesis of both 2-phenylamino-5-alkylthio-1,3,4-thiadiazole and bis-(2-phenylamino-5-alkylthio-)1,3,4-thiadiazole derivatives from phenylthiosemicarbazide and CS₂.     

2-取代硫醚-5-(3,4,5-三甲氧基苯基)-1,3,4-噻二唑类化合物的合成、结构与体外抗癌活性

以天然产物没食子酸为原料经醚化、酯化、酰肼化、成盐、闭环、硫醚化六步反应合成了6个2-取代硫醚-5-(3,4,5-三甲氧基苯基)-1,3,4-噻二唑类衍生物, 釆用铟催化下水相合成目标化合物8, 具有反应条件温和, 合成收率高的特点; 用IR, ¹H NMR, ¹³C NMR和元素分析对各化合物进行了表征及结构确证, 并用X射线单晶衍射法测定了化合物8a [2-(2-氯-5-吡啶甲基)硫醚-5-(3,4,5-三甲氧基苯基)-1,3,4-噻二唑]的晶体结构, 采用MTT法进行了新化合物抑制PC3和BGC-823癌细胞体外试验, 结果表明在5μmol•L^－1浓度下化合物8e对PC3的抑制活性为55.71%. 化合物8b对BGC-823细胞抑制活性为66.21%.     

2,5-二取代-1,3,4-噻二唑衍生物的一锅法合成、结构表征及生物活性研究

采用超声波辐射与相转移催化联用技术, 一锅法合成出了8个新的2-(1-萘乙酰氨基)-5-芳氨甲基-1,3,4-噻二唑化合物, 这种合成方法具有反应条件温和、反应时间较短、产率较高等特点. 新化合物的结构利用IR, ¹H NMR, ¹³C NMR, 1D NOE, MS和元素分析进行了表征. 人环氧酶-2 (COX-2)活性抑制实验结果表明, 目标化合物5f对COX-2具有很强的抑制活性, 抑制率高达95.59%; 化合物5g对COX-2也具有一定的抑制活性. 目标化合物无抗惊厥活性.     

Synthesis and in vitro antitumor activity of 1,3,4-thiadiazole derivatives based on benzisoselenazolone

A series of novel 1,3,4-thiadiazole derivatives based on benzisoselenazolone were synthesized and evaluated for their cytotoxicity in vitro against human liver cancer cell SSMC-7721,human breast cancer cell MCF-7 and human lung cancer cell A549 by CCK-8 assay.The results showed mat compounds 7e,7f,7h,7k,71 and 7m displayed good cytotoxicity against MCF-7 cell lines.Compound 71 exhibited the most potent antitumor activities among the tested compounds.     

含1,3,4-噻二唑环的联苯四唑衍生物的合成

通过5-芳基-2-巯基-1,3,4-噻二唑(1a～1d)与2-氰基-4'-溴甲基联苯(2)在氢氧化钾/N,N-二甲基甲酰胺体系中进行亲核取代反应,制得新化合物3a～3d,后者与(n-Bu) 3 SnCl/NaN3发生1,3-偶极环加成反应得到三甲基硒取代的四唑,再经相应后处理得四个新的含1,3,4-噻二哇类联苯四唑衍生...     

Synthesis,spectral characterization,and biological studies of 3,5-disubstituted-1,3,4-oxadiazole-2(3H)-thione derivatives

The reaction of 3,4-dichlorophenyl-1,3,4-oxadiazole-2( 3H )-thione with piperidine derivatives via Mannich reaction was used to generate eleven novel compounds in moderate to good yields. Synthesized molecules were characterized according to their structure with ¹H NMR, ¹³C NMR and FT-IR spectral foundations, which were compatible with literature informations. Antimicrobial activity and cytotoxicity studies were done by disc diffusion and NCI-60 sulphordamine B assay methods. The antimicrobial test results revealed that synthesized compounds have better activity against gram-positive species than gram-negative ones. A total analysis of the antibacterial, antifungal, and antiyeast activity revealed that newly synthesized compounds were really active against Bacillus cereus , Bacillus ehimensis, and Bacillus thuringiensis species . For cytotoxicity, among three different cancer cell lines (HCT116, MCF7, HUH7) compounds 5c, 5d, 5e, 5f, 5g, 5i, 5j and 5k were seemed especially effective on HUH7 cancer cell line via moderate to good activity. More significantly, against liver carcinoma cell line (HUH7) most of the compounds of the series ( 5c-5g and 5i-5j ) have better IC₅₀ values (IC₅₀= 18.78 µM) than 5-Florouracil (5-FU) and also compound 5d possessed 10.1 µM value, which represents good druggable cytotoxic activity. Further, the molecules were also screened for in silico chemoinformatic and toxicity data to gather the predicted bioavailibity and safety measurements.     

Design and synthesis of some new thiophene and 1,3,4-thiadiazole based heterocycles

Abstract

The reaction of 3-oxopropanenitriles with phenyl isothiocyanate in DMF containing KOH afforded the corresponding potassium salts. The latter salts were converted into ketene N,S-acetals upon acidification with hydrogen chloride. The reaction of the ketene N,S-acetals with 2-bromo-1-[5-methyl-1-(p-tolyl)-1H-1,2,3-triazol-4-yl]ethan-1-one or 3-(2-bromoacetyl)-2H-chromen-2-one gave novel thiophenes in good yields. Treatment of the ketene N,S-acetals with hydrazonyl halides afforded 1,3,4-thiadiazoles in good yields. The stereochemistry of the synthesized compounds was studied.