6-Substituted-9-(3-formamidobenzyl)-9H-purines. Benzodiazepine receptor binding activity

A series of 6-substituted-9-(3-formamidobenzyl)purines were synthesized and studied for benzodiazepine receptor (BZR) binding activity. Most of the target compounds were prepared by reaction of 6-chloro-9-(3-formamidobenzyl)-9H-purine ( 17 ) with the appropriate amine, alcohol or other nucleophilic reagent. Alternatively, the 6-cyclopropylaminopurine 5 was synthesized via the nitrobenzyl precursor 22 , and the 6-alkyl-thiopurines 14 and 15 were prepared by alkylation of the appropriate purine with 3-formamidobenzyl bromide. Purines with a variety of 6-substituents retained potent BZR binding properties, although certain bulky 6-substituents led to compounds with diminished activity. None of the compounds exhibited significant activity on a modified Geller-Seifter Conflict schedule.     

Synthesis of some heteroaryl pyrazole derivatives and their biological activities

In order to search for novel fungicides with high activity, a series of heteroaryl pyrazoles were synthesized from 5-pyra-zole formhydrazide. The structures of all new compounds were confirmed by spectroscopic methods and microanalyses. Preliminary bioassays indicated that some compounds showed fungicidal activity against Puccinia tritinia and PGR activity as well.     

Synthesis of novel thio(seleno) phosphate-phosphonates and their biological activities

In order to search for novel herbicides with high activity and selectivity, a series of thio(seleno) phosphate-phosphonate derivatives were synthesized in good yields by a one-pot procedure using tris(diethylamino)phosphine activated by iodine as the phosphorylating reagent. The structures of all compounds prepared were confirmed by spectroscopic methods and microanalyses. Preliminary bioassays indicated that some of the products possess potent and selective herbicidal activities and antiphytoviral activities against the tobacco mosaic virus (TMV). In addition, some of them exhibit significant fungicidal activities against R. Solani and P. Piricola. © 1998 John Wiley & Sons, Inc. Heteroatom Chem 9:369–375, 1998     

Nucleosides and nucleotides. 2. Synthesis of both anomers of 1-(5'-O-phosphoryl-2'-deoxy-D-ribofuranosyl)-2(1H)-pyridone

The two anomeric 1-(2′-deoxy-D -ribofuranosyl)-2(1H)-pyridones 6 and 7 were synthesized from 2-pyridone and 3,5-di-(O-p-toluoyl)-2-deoxy-D -ribofuranosyl chloride ( 2 ) via the di-O-p-toluoyl derivatives 3 and 4 using the mercuric halide procedure. Phosphorylation of the nucleosides 6 and 7 by bis-(2,2,2-trichloroethyl)-chlorophosphate gave the phosphate esters 8 and 9 together with some 2-(bis-[2,2,2-trichloroethyl]-phosphoryloxy)-pyridine 10 , which proved to be very labile. Structure and configuration of compounds 6 to 9 were established by spectral methods, the configurations being derived from the chemical shifts of the sugar protons and the splitting patterns of the anomeric protons (‘triplet-quartet rule’). The specific rotations of 3 , 4 , 6 , 7 , 8 and 9 show that the three pairs of anomers represent exceptions to Hudson's rule of isorotation. Reductive removal of the trichloroethyl groups in 8 and 9 with zinc proceeds stepwise, yielding the phosphoro-diesters 13 and 14 and the two desired anomeric 5′-nucleotides 15 and 16 . These latter were purified and characterised as the ammonium salts. Enzymatic cleavage by the 5′-nucleotidase of Crotalus adamanteus venom took place only in the ‘natural’ β-series. The ‘unnatural’ α-anomers were resistent to the enzyme. The structure of 10 was established by spectral methods and confirmed by synthesis.     

Synthesis of some 2-(heteroarylamino)benzimidazoles and their cyclization with phosgene

2-(Benzimidazol-2-ylamino)pyridine (4a) , 2-(benzimidazol-2-ylamino)pyrazine (4b) , and 2-(benzimidazol-2-ylamino)thiazole (4c) underwent a ring-closure reaction on treatment with phosgene affording 6H-pyrimido-[1′,2′:5,4][1,3,5]triazino[1,2-a]benzimidazol-6-one (1a) , 6H-pyrazino[1′,2′:5,4][1,3,5]triazino[1,2-a]benzimidazol-6-one (1b) , and 5H-thiazolo[2′,3′:4,5][1,3,5]triazino[1,2-a]benzimidazol-5-one (1c) respectively. The structure of these hitherto unknown heterocyclic systems was confirmed by their ir and mass spectra.     

3-（2-呋喃基）-4-芳基-1，2，4-三唑啉-5-硫酮的合成及生物活性

1-（2-呋喃甲酰基）-4-芳基氨基硫脲经过环化反应，制备了一系列新的化合 物3-（2-呋喃基）-4-芳基-1，2，4-三唑啉-5-硫酮类化合物，并通过元素分析和 IR，^1H NMR等波谱数据确证了上述化合物的结构。初步的生物活性实验表明其中 有些化合物的具有非常好的植物生长调节活性。     

Synthesis of 2,4,6-trisubstituted 5-(2-alkylsulfanylethyl)-pyrimidines and some their transformations

New 2,4,6-trisubstituted 5-(2-alkylsulfanylethyl)pyrimidines were synthesized by condensation of ethyl 2-(2-alkylsulfanylethyl)-3-oxobutanoates with various amidines and thiourea. Fusion of substituted 2,6-dimethylpyrimidin-4(3H)-ones with aromatic aldehydes gave the corresponding 6-styrylpyrimidines. Some 5-(2-alkylsulfanylethyl)pyrimidines were oxidized to sulfoxides, and amination of 5-[2-(butylsulfanyl)ethyl]-6-methyl-2-propylsulfanylpyrimidin-4(3H)-one with 4-aminobenzoic acid afforded 4-{5-[2-(butylsulfanyl)ethyl]-4-methyl-6-oxo-1,6-dihydropyrimidin-2-ylamino}benzoic acid.     

Synthesis of 9-(2-fluorobenzyl)-6-methylamino-9H-purine

Synthesis of 9-(2-fluorobenzyl)-6-methylamino-9H-purine ( 1 ) from nine different precursors is reported. Compound 1 was prepared by methylamination of 6-chloro-9-(2-fluorobenzyl)-9H-purine ( 4 ), by alkylation of 6-methylaminepurine ( 5 ) or form 9-(2-fluorobenzyl)-1-methyladeninium iodide ( 8 ) via the Dimroth rearrangement. Selective 2-step methylation of 6-aminopurine 6 was accomplished by hydride reduction of 6-formamidopurine 9 , 6-dimethylaminomethyleneaminopurine 10 or 6-phenylthiomethyl purine 11 to give 1. Compound 1 was also prepared by dethiation or reductive dechlorination of 2-methylthiopurine 16 or 8-chloropurine 19 , respectively, or by hydrolysis of 6-N-methylformamidopurine 12 , which was prepared from 6-dimethylaminopurine 13 by selective oxidation.     

Efficient synthesis of (+)-1,8,8a-tri-epi-swainsonine, (+)-1,2-di-epi-lentiginosine, (+)-9a-epi-homocastanospermine and (-)-9-deoxy-9a-epi-homocastanospermine from a D-glucose-derived aziridine carboxylate, and study of their glycosidase inhibitory activities

The utility of a D-glucose-derived aziridine carboxylate was demonstrated for the synthesis of polyhydroxylated quinolizidine and indolizidine alkaloids. The chemoselective reduction of 1 followed by two-carbon homologation by the Wittig reaction afforded gamma,delta-aziridino-alpha,beta-unsaturated ester 9, which on regioselective nucleophilic aziridine ring opening either by using water as a nucleophile or hydrogenation afforded delta-lactams 11/16--true synthons for the synthesis of four structurally different iminosugars, namely quinolizidine alkaloids 5b/5c, swainsonine 6b and lentiginosine 7b analogues. Glycosidase inhibitory activities of these iminosugars were investigated.     

Synthesis and biological evaluation of some novel-3-(5-substituted benzimidazol-2-yl)-5-arylisoxazolines

<正>The synthesis of a new series of 3-(5-substituted benzimidazol-2-yl)-5-arylisoxazolines(6a-h) was achieved in excellent yields by the condensation of 1-(1H-benzimidazol-2-yl)-3-(substituted phenyl)prop-2-en-1-ones(5a-h) with hydroxylamine at room temperature.These 1-(1H-benzimidazol-2-yl)-3-(substituted phenyl)prop-2-en-1-ones(5a-h) were obtained by the condensation of 2-acetyl benzimidazoles(4a-d) with different aromatic aldehydes,which in turn were obtained by the oxidation of 2-(α-hydroxy) ethyl benzimidazoles(3a-d) prepared by the reaction of o-phenylenediamines(1a-d) withα-hydroxy propionic acid 2. The synthesized compounds were characterized by their IR,~1H NMR and MS analyses.These compounds were screened for their antibacterial and antifungal activity by standard methods and found some of them active.     

Synthesis of 2-acetamido-6-O-(2-acetamido-2-deoxy-β-D-glucopyranosyl)-2-deoxy-d-glucopyranose

Conclusion The synthesis of 2-acetamido-6-O-(2-acetamido-2-deoxy--D-glueopyranosyl)-2-deoxy-D-glucopyranose was accomplished.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 630–632, March, 1971.     

Synthesis, structural elucidation and biological activities of organotin(IV) derivatives of (E)-3-(4-methoxyphenyl)-2-(4-chlorophenyl)-2-propenoic acid

A new series of di- and tri-organotin(IV) compounds with the general formula R_4?n SnL _n , where R?=?Me (1,2), Et (3), n-Bu (4,5), n-Oct (6), Ph (7) and L?=?(E)-3-(4-methoxyphenyl)-2-(4-chlorophenyl)-2-propenoate, were synthesized by reaction of silver salt of ligand or ligand acid with diorganotin dichloride/oxide and triorganotin chloride in 2:1 and 1:1 molar ratio, respectively. These compounds were characterized by elemental analyses, FT-IR, multinuclear (¹H, ¹³C, ¹¹⁹Sn) NMR and mass spectrometry. The spectroscopic results revealed that all the diorganotin(IV) compounds possess trigonal bipyramidal structures in solution and octahedral geometry in the solid state around the tin atom. A linear polymeric trigonal bipyramidal structure in the solid state and a tetrahedral environment around the tin atom in non-coordinating solvents has been proposed for the triorganotin(IV) compounds. All synthesized compounds were tested in vitro against a number of microorganisms to assess their biocidal activity. These studies revealed that ligand acid and some of its organotin compounds show promising activity against different strains of bacteria and fungi but lowered than reference drugs.