Synthesis and biological evaluation of new 3,5-di(trifluoromethyl)-1,2,4-triazolesulfonylurea and thiourea derivatives as antidiabetic and antimicrobial agents

Fluorinated 1,2,4-triazoles 3 and benzenesulfonyl urea and thiourea derivatives as well as their cyclic sulfonylthioureas 4–10 were prepared as antimicrobial agents. The chemistry involves the condensation of sulfanilamide derivatives 1 with trifluoroacetic anhydride to give N-di(trifluoroacetyl)sulfonamides 2 which upon reaction with hydrazine hydrate afforded the corresponding triazole derivatives 3. Reaction of triazole derivative 3a with isocyanates and isothiocyanates gave the corresponding ureas 4 and thioureas 5. Cyclization of thiourea derivatives with ethyl bromoacetate, 1,2-diiodoethane, diethyl oxalate and α-bromoacetophenone derivatives yielded the corresponding 4-oxothiazolidines 7, thiazolidines 8, 4,5-dioxothiazolidines 9 and thiazolines 10. Preliminary biological screening of the prepared compounds revealed significant antimicrobial and mild antidiabetic activities.     

A Study on the Stability of 5,5-Diamino-substituted-1,4,2-oxathiazoline Derivatives

5,5-Diamino-substituted-1,4,2-oxathiazoline derivatives 3 as potential prodrugs, which were easily prepared from hydroximoyl chlorides 1 and the appropriate thiourea derivatives 2, were decomposed instantaneously into isothiocyanates 4 and the corresponding urea derivatives 5 irrespective of the substituents.     

Dapson in Heterocyclic Chemistry,Part II: Antimicrobial and Antitumor Activities of Some Novel Sulfone Biscompounds Containing Biologically Active Thioureido,Carbamothioate, Quinazoline,Imidazolidine, and Thiazole Moieties

The reaction of 4,4′-diisothiocyanato-1,1-diphenylsulfone 2 with aromatic amines and phenol derivatives afforded the corresponding thioureio derivatives 3–9 , respectively. Also, the reaction of 2 with catechol gave the corresponding carbamothioate derivative 11. Quinazoline derivatives 14 and 15 were obtained in good yield via reaction of 2 with anthranlic acid derivatives. Imidazolidine biscompounds 16 and 17 were readily synthesized from the reaction of 2 with N-(4-substituted-phenyl)cyanothioformanilides. The structure of the products was confirmed from elemental analysis as well as spectral data. Most of the synthesized compounds showed remarkable antimicrobial activity compared with chloramphenicol and Grisofluvine as positive controls. Compound 6 was almost as active an antitumor agent as the reference drug Doxorubicin.     

γ-Oxo Carboxylic Acids in Heterocyclic Synthesis IV. Synthesis of Some Pyridazines Containing Phthalyl and Tosyl Amino Acids Using Dcc as the Condensing Agent

The 3(2H)-oxo-, 3(2H)-thioxo- or 3-amino-pyridazine derivatives 4, 6 and 7 were coupled with N-phthalyl- or N-tosyl-amino acids in one-step using N,N′-dicyclohexyl-carbodiimide as the condensing agent to furnish the corresponding 3-(N-phthalyl- or N-tosyl-aminoacyl)pyridazine derivatives 8–10 respectively. Hydrazinolysis of the N-phthalyl derivatives in methanol yielded the corresponding unprotected derivatives 11–13. The antibacterial activities of the prepared compounds were tested.

     

Antimicrobial and antiquorum-sensing activity of Ricinus communis extracts and ricinine derivatives

Ricinine (1), a known major alkaloid in Ricinus communis plant, was used as a starting compound for the synthesis of six ricinine derivatives; two new and four known compounds. The new derivatives; 3-amino-5-methyl-1H-pyrazolo[4,3-c]pyridin-4(5H)-one (2), and 3-amino-5-methyl-1-(phenylsulfonyl)-1H-pyrazolo[4,3-c]pyridin-4(5H)-one (3), as well as the previously prepared derivatives (4–7) were subjected for antimicrobial and antiquorum-sensing evaluation in comparison to different R. communis extracts. Acetyl ricininic acid derivative (5) showed the highest antimicrobial activity among all tested derivatives against Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeuroginosa and Candida albicans. However, compound 7 (4-methoxy-1-methyl-2-oxo-1,2-dihydropyridine-3-carboxamide) showed the highest antiquorum-sensing activity among all tested compounds and extracts. These findings proved the usefulness of ricinine as a good scaffold for the synthesis of new antimicrobial and antiquorum-sensing derivatives in spite of its poor contribution to the antimicrobial activity of the plant extracts.     

Synthetic Access to New Pyridone Derivatives through the Alkylation Reactions of Hydroxypyridines with Epoxides

General methods for the preparation of a variety of pyridone and oxypyridine derivatives are described. 2‐,3‐,4‐Hydroxy pyridine and 2‐pyridinemethanol were alkylated with ethylene‐, propylene‐, and stryrene‐oxide and epichlorohydrin in the presence of different Lewis acids as a catalyst. The best yield of 3a was achieved in the presence of CdI₂/BF₃ · OEt₂. The corresponding pyridone derivatives (3a–d, 7a–d) were obtained from the reaction of 2‐and 4‐hydroxypyridine with oxiranes in good yields, whereas oxypyridine derivatives (5a–d, 9a,b) were obtained from reactions of 3‐hydroxypyridine and 2‐pyridinemethanol with oxiranes. Chlorohydrines (3d, 5d, 7d) were easily converted to corresponding epoxy derivatives (10, 11, 12) in basic medium; then amino alcohols (13–17) were obtained from the reaction of these epoxy derivatives with amines.     

Synthesis of some heterocyclic compounds derived from indole as antimicrobial agents

Recently, indoles are considered interesting heterocyclic compounds due to their wide range of biological activities such as antimicrobial activity. Herein, some new indole derivatives containing heterocyclic moieties were synthesized using 3-chloro-1H-Indole-2-carbaldehyde (1) as a starting material, then allowed to react with compounds containing active methylene under Knoevenagel condensation and afforded the corresponding compounds (2, 3, 9). Also, the compound (1) when allowed to react with hydrazine derivatives gave the corresponding thiosemiccarbazone, semicarbazone, and hydrazone derivatives (4, 5, 6). Reaction of thiosemicarbazone derivatives with α-halognated carbonyl compounds gave the thiazolyl indole derivatives (10, 12a–b). Cyclic chalcones (11a–c) were obtained when compound (10) reacted with different aromatic aldehydes. The structures of all new synthesized compounds were confirmed on the basis of spectral analysis, IR, 1H NMR, 13C NMR, and MS spectroscopy. All synthesized compounds were evaluated for their antimicrobial activity. Compounds (2, 5, 7, 8, 11a, 12a) showed high antibacterial activity and compounds (3, 6, 9, 10, 11a, 12a) showed high antifungal activity.     

Synthesis and biological evaluation of picroside derivatives as hepatoprotective agents

Picrorhizae Rhizoma as a hepatoprotective herb, has been applied for thousands of years, and picroside was proved to be its active constituent. In this study, twelve derivatives of picroside were synthesized and the hepatoprotective activity of the derivatives was evaluated on SMMC-7721 cells. Six out of the derivatives had shown a better protective effect on H₂O₂-induced SMMC-7221 cells than picroside, and the activity of two derivatives (2 and 4) was stronger than that of the reference compound, silybin. Compound 2 shown the strongest protective effect (EC₅₀?=?6.064?±?1.295?μM).     

Addition Reactions of Glycal Esters: Access to Glycosyl Donors of Kdo,d-glycero-d-talo- and d-glycero-d-galacto-2-Octulosonic Acid Residues

ABSTRACT

Addition reactions of O-acetylated glycal esters of Kdo mono-, α-(2→8)- and α-(2→4)- linked Kdo disaccharide derivatives 1a - c with NIS in acetic acid afforded good yields of trans-diaxial as well as minor amounts of trans-diequatorial and cis-configured 2-O-acetyl-3-deoxy-3-iodo derivatives, which were efficiently reduced with Bu₃SnH/AIBN to give the corresponding per-O-acetylated Kdo methyl ester derivatives. Similar reactions of 1a with NBS or NCS furnished the trans-diaxial 2-O-acetyl-3-bromo-3-deoxy- as well as 3-chloro-3-deoxy derivatives as the main products. Reaction of 1a with NBS in aqueous MeCN provided the 2,3-trans-bromohydrin derivative 11c, which upon treatment with DBU in MeCN gave the elimination product 11 and the α-2,3-anhydro derivative 12 as a suitable donor of glycosides with D-glycero-D-talo- or D-glycero-D-galacto configuration, respectively.     

Two new dimeric naphthoquinones with neuraminidase inhibitory activity from Lithospermum erythrorhizon

The crude methanol extract of roots of Lithospermum erythrorhizon was subjected to successive chromatographic fractionation which afforded two new dimeric naphthoquinone derivatives shikometabolin E (2) and shikometabolin F (3) as well as one known compound shikometabolin A (1). The structures of compounds 1–3 were elucidated by using UV, MS, 1D and 2D NMR spectroscopic analysis. The two new dimeric naphthoquinone derivatives showed significant neuraminidase inhibitory activities.     

The Synthesis of Nitrogen-Containing Calixarene Derivatives and their Interactions with Lead Ions

Several new nitrogen-containingcalixarene derivatives have been synthesized andtheir ion-binding properties investigated byUV spectroscopy and solventextraction. These derivatives include5,11,17,23-tetra-t-butyl-25,26,27,28-tetrakis(piperidinocarbonylmethoxy)calix[4]arene (5),5,11,17,23,29,35,41,47-octa-t-butyl-49,50,51,52,53,54,55,56-octa(piperidinocarbonylmethoxy)calix[8]arene (6) and5,11,17,23,29,35,41,47-octa-t-butyl-49,50,51,52,53,54,55,56-octa(N,N-diethyl-car-bamoyl-methoxy)calix[8]arene(7). The UV spectra of and 7revealed they had an ability to transform tight lead picrate ionpairs into separated ones by complexationwith Pb²⁺ in tetrahydrofuran.Both derivatives give 1 : 1 complexes with Pb²⁺. Extraction studies showed that these derivativescould efficiently extract Pb²⁺ (as picrate salts) from the aqueous phase into chloroform. Theextractability of these derivatives were also compared with that ofthe oxygen-containing ester derivative calix[8]arene 2 and the other two nitrogen-containingcompounds 8 and 9.     

Design,synthesis of new pyrimidine derivatives as anticancer and antimicrobial agents

A new series of 6-aryl-5-cyano thiouracil derivatives were synthesized. Cyanouracil 1 was condensed with monochloroacetic acid and different aldehydes to give thiazolopyrimidine 2. On the other hand, treatment of cyanouracil 1 with 2-chloro-N-substituted-phenylac etamide afforded 4. Hydrazinolysis of 6 afforded the hydrazino derivatives 7 which upon reaction with different electrophilic reagents such as acetic anhydride, benzoyl chloride, and carbon disulfide yielded pyrimidine derivatives 8–15. Some of the new derivatives were explored for their antimicrobial activities. Compounds 7 and 9 have a promising activity, relatively equipotent to the reference drug. All of the new synthesized compounds were tested in vitro for their antiproliferative activities against HePG-2 and MCF-7 cell lines. Compounds 7, 9, and 2d displayed potent growth inhibitory effect toward the two cell lines more than the standard drug 5-FU. Furthermore, a docking study of the most active compounds was performed with thymidylate synthase enzyme.     

新型四硫富瓦烯硫杂冠醚衍生物的合成

在高度稀释条件下, 经4,5-二溴甲基-1,3-二硫杂环戊烯-2-硫酮(7)和多缩乙二醇的1,ω-二巯基衍生物的缩合反应, 方便地合成了4,5-位带二硫杂冠醚残基的2-硫代-1,3-二硫杂环戊烯的衍生物8a～8d, 中间体硫杂冠醚8c～8d的合成中有明显的“模板效应”. 在亚磷酸三乙酯存在下, 8a～8d经自偶联生成新型的对称双臂四硫富瓦烯(TTF)硫杂冠醚衍生物10a～10d, 而与4,5-二甲硫基-1,3-二硫杂环戊烯-2-酮(9)经交叉偶联生成新型的非对称单臂四硫富瓦烯硫杂冠醚衍生物11a～11d. 用循环伏安法研究了上述目标化合物的电化学性质和离子传感性质.     

5-Anthracenylidene and 5-(4-Benzyloxy-3-methoxy)benzylidene-hydantoin and 2-Thiohydantoin Derivatives,Synthesis, and S-Alkylation

Abstract

5-Anthracenylidene- and 5-(4-benzyloxy-3-methoxy)benzylidene-hydantoin and 2-thiohydantoin derivatives 3a-g were prepared by condensation of anthracene-9-carboxaldehyde and 4-benzyloxy-3-methoxybenzylaldehyde with hydantoin and 2-thiohydantoin derivatives. Compounds 3a, b, f undergo Mannich reaction with formaldehyde and morpholine to give the corresponding Mannich products 4a–c. For the synthesis of alkylmercaptohydantoin 5a–o, the potassium salt of compounds 3a, b, e, f were reacted with an alkylhalide, either methyl iodide, phenacyl bromide, ethyl bromo acetate, allyl bromide, or methallyl bromide, under stirring at room temperature to afford the alkylmercaptohydantoins 5a–o. Acid hydrolysis of compounds 5a–c afforded the corresponding arylidene-hydantoin derivatives 3c, d, g. 2-Methylmercapto-hydantoin derivatives 5a, c were reacted with some secondary amines such as morpholine or piperidine to afford 5-(4-benzyloxy-3-methoxy)benzylidene-2-morpholino- or piperidino glycocyamidine derivatives 7a, 5-anthracenylidene-2-morpholin-, or piperidino glycocyamidine derivatives 7b, c.

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.

GRAPHICAL ABSTRACT     

Derivate der 5,6-Dihydro-2H-pyran-3-carbonsäure

Summary Some derivatives of 5,6-dihydro-2H-pyran-3-carboxaldehyde (7) and of its oxidation product 5,6-dihydro-2H-pyran-3-carboxylic acid (8) have been prepared. The aldehyde derivatives as well as the amides and esters of8 have been tested in an insecticidal/fungicidal/acaricidal screening programme. The methylester35 shows a distinct knock down effect against the fruit flyDrosophila melanogaster.

     

New Synthetic Routes to 1,3,4-Thiadiazole Derivatives

Different new 1,3,4-thiadiazolopyridine derivatives (6, 8, 20, 28, and 42) were synthesized from 5-cyanomethyl-1,3-4-thiadiazole (1) and activated nitriles. Also, spiro indolono-thiadiazolopyridine (12) was obtained from the reaction of (1) with 2-(2-oxoindolin-3-ylidene)malononitrile (10). Other heterocyclic derivatives at position-5 in the thiadiazole ring were obtained for possible use as antimicrobial agents.     

Synthesis of a series of triple-bridged cyclotriphosphazene hexa-alkoxy derivatives and investigation of their structural and mesomorphic properties

Triple diamino-bridged cyclotriphosphazene (1) was reacted in a 1:8 stoichiometry with the sodium derivatives of long-chain diols [1-octanol, 1-decanol, 1-dodecanol, 1-hexadecanol] tetrahydrofuran (THF) at room temperature to form hexa-substituted cyclotriphosphazene derivatives (2, 3, 4 and 5, respectively), whose mesomorphic behaviours were investigated for their possible applications as liquid crystals. The cylindrical-type cyclotriphosphazene derivatives (2–5) were characterised by mass and elemental analyses and by Fourier transform infrared spectroscopy (FT-IR), ¹H and ³¹P {¹H} NMR spectroscopies. The thermal and mesomorphic properties were investigated by differential scanning calorimetry and by polarising optical microscopy, respectively. It was found that liquid crystal materials could be obtained from compounds 3 and 4 with alkoxy chains rather than using aromatic ring(s) as mesogens as published previously.     

Synthesis of novel triazolothione,thiadiazole, triazole-functionalized furo/thieno[2,3-b]pyridine derivatives and their antimicrobial activity

A series of novel triazolothione, thiadiazole, triazole-functionalized furo/thieno[2,3-b]pyridine derivatives 9a–l, respectively, were prepared starting from 2 (1H) pyridone 3 through selective O/S-alkylation followed by Thorpe–Ziegler cyclization to form furo/thieno[2,3-b]pyridine derivatives 6. Compounds 6 on reaction with hydrazine hydrate resulted carbohydrazide derivatives 7 and further reacted with diverse substituted phenyl isothiocyanates to form phenyl hydrazine carbothiamide derivatives 8. Each compound 8 is independently reacted in presence of NaOH, H₂SO₄, and N₂H₄.H₂O to form triazolothione, thiadiazole, triazole-functionalized furo/thieno[2,3-b]pyridine derivatives 9a–l, respectively. All the products 9a–l were screened against Gram +ve, Gram –ve bacteria and fungal strains. Compounds 9c–h showed high activity against Bacillus subtilis microbial-type culture collection (MTCC) 121 at <8.0 micromolar concentration. Promising compounds further screened for minimum bactericidal concentration against B. subtilis MTCC 121 using ciprofloxacin as standard and found to show very good activity. These compounds also screened for biofilm inhibition activity against B. subtilis MTCC 121 using erythromycin as standard and confirmed the high activity.     

SYNTHESIS OF 1- AND 3-C-(AMINOMETHYL)-1,2,3,4,5-CYCLOHEXANEPENTOLS FROM (+)-epi-QUERCITOL[1]

Oxidation of three di-O-isopropylidene derivatives 2a—4a, newly derived from (+)-epi-quercitol (1), with acetic anhydride in DMSO gave the corresponding ketones 5—7, which underwent aldol-type condensation with nitromethane under basic conditions to give selectively the protected derivatives 8a—10a of C-nitromethyl-1,2,3,4,5-cyclohexanepentols, respectively. On treatment with diazomethane in DMSO, the ketones 6 and 7 gave single spiro epoxides 11 and 12, the structures of which were confirmed by converting them into new C-(azidomethyl)cyclohexanepentols 16 and 17. The nitro compounds were hydrogenated in the presence of Raney nickel to give the amines isolated as the N-acetyl derivatives. Deprotection gave three new 1- and 3-C-aminomethyldeoxyinositols 15c—17c. The aminocyclitols obtained and their N-acetyl derivatives were assayed for inhibitory activity against examples of glycosidases.     

A Convenient Route to 1,3,4-Thiadiazoles,Thiazolidinone, Thiazoles,Pyridones, Coumarins,Triazolo[5,1-c]triazines,and Pyrazolo[5,1-c]triazines Incorporating Pyrazolone Moiety and Their Use as Antimicrobial Agents

Condensation of 4-acetyl-5-methyl-2-phenyl-2,4-dihydropyrazol-3-one (1) with hydrazine derivatives (2a–d) afforded hydrazone derivatives (3a–d), which reacted with alkyl halides 4a–c to give bis(alkylthio)methylene derivatives (5a–e). Also, 3a,b reacted with hydrazonyl halides 6a–d to give 1,3,4-thiadiazole (7a–d). Cyclization of 3c with ethyl bromoacetate and haloketones gave thiazolidinone and thiazole derivatives (8, 10a,b) respectively. Treatment of hydrazone (3d) with benzylidine malononitrile 13a,b gave pyridine (14a,b). In addition, cyclocondensation of 3d with phenolic aldehydes furnished coumarin derivatives (16a–c). Coupling of 3d with heterocyclic diazonium salts gave triazol[5,1-c]triazine (20) and pyrazolo[5,1-c]triazine (22). Some of the prepared products showed potent antimicrobial activity.