Laser photolysis of 1-(4-nitrophenyl)-3-methylpyrazole and 1-ethyl-3-(4-nitrophenyl)-5-chloropyrazole

The spectral kinetic characteristics of the triplet states of 1-(4-nitrophenyl)-3-methylpyrazole (1) and 1-ethyl-3-(4-nitrophenyl)-5-chloropyrazole (2) were studied by the laser nanosecond photolysis technique in different solvents. The triplet lifetimes (τ_T) of molecules 1 and 2 were found to depend strongly on the solvent nature. An increase in τ_T by approximately two orders of magnitude on going from nonpolar and polar aprotic solvents (τ_T ≤ 15 ns) to aqueous-acetonitrile solutions (τ_T = 1100 ns for a volume acetonitrile to water ratio of 1 : 3) was analyzed, taking into account the influence of the medium on the relative contribution of the n,π*- and π,π*-configurations to the lowest triplet state. __________ Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1115–1119, May, 2005.     

Asymmetric Synthesis of （-）-（4R, 5R）-4-[5-（Benzo[1, 3]dioxol-5-yl）-4- hydroxyl- 1-（pyridin-2-yl）-4, 5-dihydro- 1H-pyrazol-3-yl]benzamide

For discovering novel small molecule inhibitors of transforming growth factor-β1(TGF-β1)type-I receptor(ALK5),we designed1,3,5-triaryl-4-hydroxyl-4,5-dihydro-1H-pyrazole(1)as target compound,mimic the structure of SB-431542which is a2-pyridyl substituted triarylimiazole inhibitor of ALK51.Racemic compound1showed moderate ALK5inhibitory activity in luciferase reporter assays[inhibition(%control):0.1umol/L8.79%;1umol/L19.05%].To investigate the influence of the absolute configuration of…     

4-取代苯次甲亚胺-5-(1-苯基-3-甲基-5-氯吡唑)-2H-1,2,4-三唑-3-硫酮的合成

以乙醇为溶剂,冰醋酸为催化剂,4-氨基-5-(1-苯基-3-甲基-5-氯吡唑)-1,2,4-三唑-3-硫酮(1)与芳醛经缩合反应合成了7个新型的4-取代苯次甲亚胺-5-(1-苯基-3-甲基-5-氯吡唑)-4H-1,2,4-三唑-3-硫酮(3a~3g),收率66%~74%,其结构经1H NMR,IR及元素分析表征。合成4-(苯次甲亚胺)-5-(1-苯基-3-甲基-5-氯吡唑)-2H-1,2,4-三唑-3-硫酮(3a)的最佳反应条件为:以乙醇为溶剂,乙酸为催化剂,1 10 mmol,n(苯甲醛)∶n(1)=1.2,于75℃反应3 h,产率74%。     

Synthesis and Crystal Structure of 1，5－Bis（1＇－phenyl－3＇－methyl－5＇－pyrazolone－4＇）－1－（4＇－aminobutand－1＇－imino）－5－pentaneone

ＳｙｎｔｈｅｓｉｓａｎｄＣｒｙｓｔａｌＳｔｒｕｃｔｕｒｅｏｆ１，５－Ｂｉｓ（１＇－ｐｈｅｎｙｌ－３＇－ｍｅｔｈｙｌ－５＇－ｐｙｒａｚｏｌｏｎｅ－４＇）－１－（４＇－ａｍｉｎｏｂｕｔａｎｄ－１＇－ｉｍｉｎｏ）－５－ｐｅｎｔａｎｅｏｎｅ￥ＹａｎｇＬｕ－Ｑ...     

5-(1-Alkenyl)-1, 3, 4-oxadiazol-2(3H)-one

3-(2-alkenoyl)-thiocarbazic acid O-methyl esters 1 are desulfurated by bromine and the unknown intermediates are transformed by alkali to 5-(1-alkenyl)-1, 3, 4-oxadiazol-2(3H)-ones ( 2 ). This type of oxadiazolone substitution is not realizable by the common ring closure of hydrazides with phosgene due to pyrazolidinone ring closure of unsaturated acids with hydrazine.     

Formation and structure of 1-Amino-4-methyl-4-(4-methyl-5-phenyl-1H-pyrazol-3-ylamino)-3-phenyl-4,5-dihydro-1H-pyrazol-5-one

The title compound 3 was obtained during the rearrangement of isoxazol-5-yl hydrazine 1 to 1-aminopyrazolone 2 at 115°. X-ray analysis of the corresponding benzylidene derivative allowed us to achieve the structure assignment.     

5-(4-氯苯基)-1-(2,4-二氯苯基)-4-甲基吡唑-3-羧酸的合成

对氯苯丙酮经三甲基氯硅烷保护后与草酸单乙酯单酰氯缩合制得4-(4-氯苯基)-3-甲基-2,4-二氧代丁酸乙酯(4);4与2,4-二氯苯肼盐酸盐缩合成腙、再经分子内环合、水解合成了制备利莫那班的关键中间体——5-(4-氯苯基)-1-(2,4-二氯苯基)-4-甲基吡唑-3-羧酸,总收率30.3%,其结构经1HNMR和MS确证。     

Synthesis and Crystal Structure of 2（1-Phenyl-3-methyl-5-chloro-1H-pyrazol-4-yl）-3-（1-naphthoylamido）-4-thiazolidinone

1INTRODUCTIONManypyrazolederivativeshavebeenreportedtoshowvariousbiologicalactivitiestobeusedasbactericide[1],fungicide[2],herbicide[3],insecticide[4]andvirucide[5]agents.Inaddition,4-thiazolidinoneplaysavitalroleowingtoitswiderangeofbiologi-calactivities…     

Synthesis and Spectrophotometric Studies of 2-(1, 3, 4 -Triazolylazo) -5-Diethylamino Phenol and 2-(5-Carboxy-1, 3, 4-Triazolylazo) -5- Diethylamino Phenol

Inasearchfornewsensitiveandselectiveorganicreagents,athoroughstudyofsomeofthequinolylazo,pyridylazocompoundshasbeenreported'-'.Buttriazolylazocompoundshavenotbeenstudied.Inthispapef,2-(l,3,4-triazolylazo)-5-diethyIaminophenol(TZAPN)and2-(5-carboxy-l,3,4-triazoiylazo)-diethyIaminophenoI(CTZAPN)wereprepared,theconditionsofthisreactionwithcobaltwerestudied.Itwasfoundthatthereagentshadhighsensitivityandselectivityinthedeterminationofmicrogramamountsofcobaltundertheconditionsestablished.Thest…     

Syntheses and Structural Characterization of 1-（4-Phenyl-2-thiazolyl）-3-（4-methylphenyl）-5-（2-furyl）-4,5-dihydro-（1H）-pyrazole and 1-（4-（4-Fluoro）phenyl-2-thiazolyl）-3-（4-methyl-phenyl）-5-（2-furyl）-4,5-dihydro-（1H）-pyrazole

The title compounds were synthesized and characterized by IR,1H-NMR,Mass and elementary analysis and single-crystal X-ray diffraction.In 1a,intermolecular C-H…π interactions produce a three-dimensional network.In 1b,intermolecular C-H…O hydrogen bonds generate an R22(22) ring.The hydrogen bonding is supported by C-H…π interactions.     

Synthesis and structure of 1-(4-chlorophenyl)-3-(5-methyl-1, 3-dioxan-5-yl)-(1,2),(3,4)-diepoxybutane

The synthesis and X-ray structural study of 1-(4-chlorophenyl)-3-(5-methyl-1,3-dioxan-5-yl)-(1,2), (3,4)-diepoxybutane are described.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 715–718, April, 1995.     

Synthesis of ethyl (±1)-(e)-5-(4- and 5-(3-hydroxy-1-octenyl)-1-methyl-2-imidazolin-2-yl)-5-thia pentanoates

The racemic title compounds 1a,b and 2a,b were prepared from L-asparagine.     

Molecular and crystal structure of 4-acetyl-3-(5-nitrofurfuryl)-1-(4-chlorobenzylidene)-thiosemicarbazide

Krasnodarsk Polytechnical Institute. Translated from Zhurnal Strukturnoi Khimii, Vol. 33, No. 3, pp. 149–151, May–June, 1992.