Synthesis of Some New Pyridine and Pyrimidine Derivatives Containing Benzothiazole Moiety

A variety of pyridine and pyrimidine rings incorporating benzothiazole moiety were synthesized by reaction of 1‐(2‐benzothiazolyl)‐1‐cyano‐3‐chloroacetone ( 1 ) with 2‐pyridone, 2‐thioxopyridine, thiouracil, and 2‐thioxopyrimidine derivatives to give compounds 7,9‐dimethylfuro[2,3‐b:4,5‐b′]dipyridin‐4‐ol 5 , 4, 6‐diphenylthieno[2,3‐b]pyridin‐2‐yl 9 , 2‐(benzo[d]thiazol‐2‐yl)‐2‐(7‐substituted‐5‐oxo‐5H‐thiazolo[3,2‐a]pyrimidin‐3‐yl)acetonitriles 12a and 12b , pyrimido[2,1‐b][1,3]thiazepine‐3‐carboxamide 15 , and benzo[4,5]thiazolo[3,2‐b]pyridazine‐3‐one 20 , respectively.     

Synthesis and Antibacterial Activity of Some New S-Triazole Derivatives

Abstract

Alkylation of 4-anilino-5-phenyl-4H-1,2,4-triazole-3-thiol (1) with some halo compounds yielded the corresponding sulfides 2a–f. Some sulfides 2e,f were cyclized to give triazolothiadiazines 3 and 4. Triazolothiadiazoles 5 and 6 were prepared through the reaction of compound 1 with carbon disulfide or ethyl orthoformate, respectively. Treatment of compound 1 with ethyl chloroformate or phenyl isothiocyanate yielded triazolo-thiadiazole and triazole 9 and 10, respectively. Reaction of compound 1 with Lawesson's reagent gave triazolothiadiazaphosphole derivative 11. Also, compound 1 underwent cyclocondensation reactions with some bidentate reagents to give triazolothiazines 4, 12, and 13. Triazolo-thiazepines and triaziepine 14–16 were synthesized via the reaction of compound 1 with β-ketoesters or ethyl cyanoacetate. Tricyclic systems 19 and 20 were prepared through the reaction of compound 4 with the appropriate reagent. Some synthesized compounds were tested for antibacterial activity.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

新型薁类-1-酰腙化合物的合成及抗菌活性研究

为了合成和研究具有薁类结构物质的新的生物活性, 以1-薁类羧酸甲酯为起始原料, 经过酰肼化、与芳香醛及酮类化合物的缩合, 合成了含有酰腙类结构的薁类衍生物, 其结构经1H NMR, IR和元素分析确证. 对所得化合物进行了抗菌活性测试, 初步表明它们具有一定的活性.     

Utility of Enaminonitriles in Heterocyclic Synthesis: Synthesis of Some New Pyrazole,Pyridine, and Pyrimidine Derivatives

The starting (1,5‐dimethyl‐3‐oxo‐2‐phenyl‐2,3‐dihydro‐1H‐pyrazol‐4‐yl)carbonohydrazonoyl dicyanide ( 2 ) was used as key intermediate for the synthesis of 3‐amino‐2‐(1,5‐dimethyl‐3‐oxo‐2‐phenyl‐2,3‐dihydro‐1H‐pyrazol‐4‐ylazo)‐[3‐substituted]‐1‐yl‐acrylonitrile derivatives ( 3 – 10 ). In addition, nitrile derivative 2 reacted with hydrazine hydrate or malononitrile to afford the corresponding 3,5‐diaminopyrazole 11 and enaminonitrile derivative 13 , respectively. On the other hand, compound 3 was subjected to react with malononitrile, acetic anhydride, triethylorthoformate, N,N‐dimethylformamide (DMF)‐dimethylacetal, thiourea, and hydroxylamine hydrchloride to afford antipyrine derivatives 16 – 21 . Moreover, the reaction of enaminonitrile 3 with carbon disulfide in pyridine afforded the pyrimidine derivative 22 , whereas, in NaOH/DMF followed by the addition of dimethyl sulphate afforded methyl carbonodithioate 24 . The reaction of enaminonitrile derivatives 3 – 5 with phenylisothiocyanate afforded the thiopyrimidine derivatives 25a – c . Finally, the enaminonitrile 4 reacted with 3‐(4‐chloro‐phenyl)‐1‐phenyl‐propenone to afford the pyridine derivative 27 . The newly synthesized compounds were characterized by elemental analyses and spectral data (IR, ¹³C‐NMR, ¹H–NMR, and MS).     

Synthesis of Some New Fluorine Containing Thiadiazolotriazinones as Potential Antibacterial Agents

2,4-dichloro-5-fluorophenyl, 4-fluoro-3-(Phenoxy)phenyl, 4-fluorophen-yl groups are known pharmacophores and can be used in the synthesis of new biologically active molecules. Therefore, 4-amino-6-arylmethyl-3-mercapto-1,2,4-triazin5(4H)-ones 1 are condensed with 3-phenoxy-4-fluoro-benzoic acid, 2,4-dichloro-5-fluorobenzoic acid, and 4-fluorobenzoic acid 2 to give 7-substituted-3-arylmethyl-4H-1,3,4-thiadiazolo[2,3-c]-1,2,4-triazin-4-ones 3 . Phosphorous oxychloride was used as cyclizing agent. All the newly synthesized compounds 3a-l was screened for their antibacterial activities. Most of them showed promising activity in the range of 10 w g/mL concentrations.     

Synthesis and Antibacterial Activity of Some New Derivatives of Thiosemicarbazide and 1,2,4-Triazole

Abstract

In a reaction of hydrazides of cyclohexylacetic acid 1 and phenylacetic acid 2 with isothiocyanates, respective thiosemicarbazide derivatives 3–18 were obtained. Further cyclization with 2% NaOH led to the formation of 5-(cyclohexylmethyl/benzyl)-4-substituted-2,4-dihydro-3H-1,2,4-triazole-3-thiones 19–34. Structures of all new products were confirmed by analytical and spectroscopic methods. All compounds were screened for their in vitro activity against some species of bacteria and fungi.

[Supplementary materials are available for this article. Go to the publisher's online edition ofPhosphorus, Sulfer, and Silicon and the Related Elements for the following free supplemental files: Additional figures and tables.]     

Synthesis and Microbial Studies of New Pyridine Derivatives-Ill

2-Amino substituted benzothiazole 4a--4I and p-acetamidobenzenesulfonyl chloride 2 were used to prepare 2-（p-aminophenylsulfonamido） substituted benzothiazole 6a--6I using mixture of pyridine and acetic anhydride which formed an electrophilic complex （N-acetyl pyridinium） to facilitate condensation to give desired product by removal of HC1. 2-{p-[（3-Carboxypyrid-2-y1）amino]phenylsulfonamido}benzothiazoles 8a--81 were synthesized from 2-chloropyridine-3-carboxylic acid 7 and 6a--6I in 2-ethoxy ethanol using Cu-powder and K2CO3. Acid chlorides 9a--91 were condensed with 2-hydroxyethyl piperazine 10 and 2,3-dichloropiperazine 11 for amide deriva- tives 2-（p-（（3-（4-（2-hydroxyethy1）piperazin-1-ylcarbonyl）pyrid-2-y1）amino）phenylsulfonamido）benzothiazoes 12a -121 and 2-{p-[3-（2,3-dichloropiperazin-l-ylcarbonyl）pyrid-2-ylamino]phenylsulfonamido}benzothiazoles 13a- 131 respectively. The structures of the new compounds have been established on the basis of their chemical analysis and spectral data （IR, 1↑H NMR and mass）. All the compounds have been screened for their antibacterial and antifungal activities.     

Nucleosides: Synthesis of Some New Naphthimidazole Ribonucleosides as Potential Antibacterial Agents

Reaction of 2-trifluoromethyl- or 2-cyanonaphth[2,3-d] imidazole (1 or 2) with 1-O-acetyl-2,3,5-tri-O- benzoyl-β-D-ribofuranose (3), using the triflate or fusion method afforded 2-trifluoromethyl-1-(2,3,5-tri- O-benzoyl-α-D- or -β-D-ribofuranosyl)naphth[2,3-d]imidazole (4 or 6) and 2-cyano-1-(2,3,5-tri-O-benzoyl-α-D- or β-D-ribofuranosyl)naphth[2,3,-d] imidazole (5 or 7), respectively. The products 4 and 5 or 6 and 7 were separated by chromatography on silica gel. Treatment of the blocked nucleosides 4-7 with methanolic NH₃ at 0 °C furnished the deblocked nucleosides 8-11 respectively. Treatment of 10 with 5% NH₃ (aq) at 60 °C gave 11. Structural elucidation is based on elemental analysis, UV, FAB-MS and ¹H NMR spectra. Compounds 4-11 were subjected to antibacteial testing. Compounds 5, 7 and 10 have significant activity against Staphylococous aureus (gram positive) and Esherichia coli (gram negative) bacteria, whereas the other tested compounds showed no significant activity.     

芘基查尔酮的合成及三阶非线性光学性质

合成了一种新的具有潜在应用价值的非线性光学(NLO)有机材料1-(芘-1-基)-3-(4-二甲氨基苯基)丙烯酮(PMAK),并通过 NMR、IR、MS和元素分析等技术手段进行了表征。 采用溶液Nd:YAG激光技术测定了PMAK的三阶非线性光学性质并确定了相关参数。 纳秒实验结果:折射率n₂=-3.5×10^-17 m²/W,吸收系数β=7.0×10^-10 m/W,极化率χ⁽³⁾=2.54×10^-11 esu,分子超极化率γ=3.44×10^-30 esu;皮秒实验结果:n₂=-2.8×10^-18 m²/W,β=8.3×10^-11 m/W,χ⁽³⁾=2.49×10^-12 esu,γ=3.33×10^-31 esu。     

Synthesis and Antibacterial Evaluation of Some New Thiazole‐Based Polyheterocyclic Ring Systems

2‐Cyanoacetamido‐thiazole ( 1 ) was employed as a key for the construction of 6‐cyano‐7‐oxo‐7H‐thiazolo[3,2‐a]pyrimidine ( 4 ) which underwent reaction with hydrazine, malononitrile, ethyl cyanoacetate, and/or various 1,3‐bi‐nuclophilic reagents furnished the corresponding tri‐heterocyclic and tetra‐heterocyclic ring systems 5 – 12 . In addition, the reactions of 1 with various types of arylidene‐malononitriles and/or ethyl 3‐aryl‐2‐cyanoacrylates yielded the corresponding 1‐thiazolyl‐pyridine derivatives 16 and 20 , respectively. Furthermore, treatment of the precursor 1 with carbon disulfide and methyl iodide afforded the ketene dithioacetal derivative 21 which cyclized upon heating with hydrazine and/or 2‐aminobenzimidazole into the corresponding derivatives of N‐(thiazol‐2‐yl)‐1H‐pyrazole‐4‐carboxamide 22 and N‐(thiazol‐2‐yl)benzimidazo[1,2‐a]‐pyrimidine‐3‐carboxamide 23 . The antibacterial properties of these thiazole‐based heterocycles were examined against panel of two bacterial strains.     

Synthesis of Some New Imidazo[4,5-B]Pyridine Derivatives Using 2-Cyanomethyl-1-Methyl-1H-Imidazo[4,5-B]Pyridine

Abstract

The reactions of 2-cyanomethyl-1-methyl-1H-imidazo[4,5-b]pyridine with isothiocyanates, nitroso compounds, acid chlorides, and thioglycolic acid were investigated. New imidazo[4,5-b]pyridine derivatives with various substituents in 2-position and derivatives of the new pyrrolo[2′,1′:2,3]imidazo[4,5-b]pyridine ring system were synthesized. The compounds obtained were tested in vitro for their tuberculostatic activity.     

Synthesis and Antibacterial Activity of New Diaryldiamines

Several new quinolines and quinazolines ( 4, 10, 13 ) have been synthesized from cheap and readily available chemicals through a series of simple chemical transformations. Most of the synthesized compounds have been evaluated for antibacterial activity against Gram positive and Gram negative strains. Some of the synthesized compounds displayed interesting activity but not very promising for further development.     

新型卟啉吡啶季铵盐的合成与应用

采用微波技术合成了3种新型吡啶卟啉季铵盐:溴化5-[4-N-(对硝基)苄铵基吡啶基]-10,15,20-三(4-N-吡啶基)卟啉、氯化5-[4-N-(对甲氧基)苄铵基吡啶基]-10,15,20-三(4-N-吡啶基)卟啉和氯化5-[4-N-(对氯)苄铵基吡啶基]-10,15,20-三(4-N-吡啶基)卟啉.化合物的结构采用紫外可见光谱、红外光谱、核磁共振谱、质谱、元素分析测试技术得到确认.在分光光度法测定水中的痕量铜离子的显色反应中,配合物的表观摩尔吸光系数都在1×105L/(mol·cm)以上,是一种高灵敏度显色剂.该卟啉试剂具有显色和表面活性剂双重功能,应用于环境水样中铜的测定得到了满意的结果.     

中氮茚类羧酸化合物的合成及抑菌活性

合成了8个中氮茚类羧酸化合物, 产物经红外、 核磁、 质谱及元素分析表征, 并研究了其抑菌性能. 结果表明, 化合物3a, 3c, 5a, 5c和5d对大肠杆菌有一定抑制作用, 化合物3a和3c对金黄色葡萄球菌有抑制作用. 其中化合物3c对所选2个菌种均表现出较好的抑菌性能.     

Synthesis and Antibacterial Acivity of Some Novel Pyrimidine-Based Heterocycles

Russian Journal of General Chemistry - Cyclization of 1,2-diamino-4(4-chlorophenyl)-6-oxo-1,6-dihydropyrimidine-5-carbonitrile 2 with a variety of electrophilic reagents results in formation of a...     

新型含吡啶酰胺基希夫碱多齿配体的合成,光谱,晶体结构及抑菌活性研究

采用稀释法与胺5倍过量合成了一种新型的含吡啶环的开链二胺1a（N，N′-双(2-氨基乙基)－2，6-吡啶二甲酰胺）。此外，合成了六个新型多齿希夫碱配体N，N′－双(β－R－苯甲醛亚胺基乙基)－2，6－吡啶二甲酰胺[其中，R=H(2a)，o-OH(2b)，p-OH(2c)，m-NO₂(2d)，p- N(CH₃)₂(2e)]及N，N′-双[γ-水杨醛亚胺基正丙基]－2，6－吡啶二甲酰胺2f。通过元素分析,紫外－可见光谱，红外光谱，氢核磁共振谱及质谱对化合物进行了表征。通过化合物2e的单晶结构X－射线单晶衍射分析表明该晶体属于立方晶系P－1空间群，其晶胞参数为：a=11.010(2) nm，b=13.865(3) nm，c=9.6537(19) nm，α=102.77(2)º，β=92.07(3)º，γ=87.98(3)º，V=1435.7(5) nm³，Z=2，D_c=1.230 mg•cm^-3，M_r=531.66。微量热法检测了化合物对大肠杆菌的抑制作用，并初步分析了化合物结构与抗菌活性之间的关系。实验结果表明，所有化合物都对大肠杆菌有抑制作用，其中水杨醛希夫碱的抑菌活性最好。     

Synthesis,Reactions, and Pharmacological Evaluations of Some Novel Pyridazolopyridiazine Candidates

Herein, we report the synthesis, characterization, and preliminary pharmacological activity of a new series of substituted pyrazolopyridazine derivatives. Compound 1 was reacted with ethoxymethylene malononitrile 2 in refluxing ethanol to give the corresponding compound 3 , which was treated with hydrazine hydrate or formamide to give pyrazolo[3,4‐c]pyrazole 4 and pyrazolo pyrimidine 5 derivatives, respectively. Also, compound 3 was reacted with NH₄SCN or carbon disulphide or ethyl acetoacetate to yield the corresponding pyrazolo derivatives 6 , 7 , 8 , respectively. Additionally, compound 3 was reacted with triethyl orthoformat in acetic anhydride to give 9 , which was treated with hydrazine hydrate to give hydrazino derivative 10 . The latter compound transformed into the pyrazolo[4,3‐e][1,2,4]triazolo[1,5‐c]‐pyrimidine 11 via refluxing with acetic anhydride. Finally, compound 9 was reacted with benzoic acid hydrazide or mercapto acetic acid to give compounds 12 and 13 , respectively. The latter compound was treated with refluxing ethanolic sodium ethoxide solution to afford the pyrazolothiazolopyrimidine 14 . Some of the compounds exhibited better activities as anti‐inflammatory and antimicrobial agents than the reference controls. The detailed synthesis, spectroscopic data, anti‐inflammatory, and antimicrobial activities of the synthesized compounds was reported.     

高分子吡啶季铵盐的抗菌性能及机理的探讨

高分子吡啶季铵盐的抗菌性能及机理的探讨;高分子抗菌剂;吡啶季铵盐;抗菌机理;杀菌     

Synthesis and Antibacterial Activity of New Cephalosporin Compounds

The fourth generation cephalosporin cefepime I exhibited potent antibacterial activity with board antibacterial spectrum1,2.Based on the structure of cefepime,we synthesized its analogs Ia having fluoro atom at the aminothiazolyl oxime moiety at the7-position of the cephem nucleus,and Ib possessing1-(2-fluoroethyl)pyrrolidium methyl group at the3-position.It was reported that cephalosporin derivatives with a quaternary ammonium moiety at the3-position of the cephem nucleus,showed enhanced ant…