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.     

Synthesis and Crystal Structure of Dimethyl-3-（4-bromophenyl）-1-phenyl-4,5-dihydro-1H-pyrazole-4,5-dicarboxylate

The title compound (C19H17BrN2O4) was synthesized via a one-pot procedure starting from 4-bromobenzaldehyde, dimethyl acetylenedicarboxylate (DMAD) and phenylhydrazine with pyridine as the catalyst. Its structure was determined by single-crystal X-ray diffraction analysis. The crystal belongs to the monoclinic system, space group P21/c with a = 11.115(3), b = 8.090(2), c = 20.211(5) , β = 97.032(5)°, V = 1803.7(8) 3, Z = 4, Mr = 417.25, Dc = 1.536 g/cm3, μ = 2.306 mm-1, F(000) = 852, the final R = 0.0403 and wR = 0.0895 for 2215 observed reflections with I 2σ(I).     

Synthesis of 4,5-dihydro-4-phenyl-3H-1,3,4-benzotriazepines

Several 4,5-dihydro-4-phenyl-3H-1,3,4-benzotriazepines were synthesized by conversion of 1-[(2-nitrophenyl)methyl]-1-phenylhydrazine to either 1-[(2-aminophenyl)methyl]-1-phenylhydrazine or 1-[(2-aminophenyl)-methyl]-2-methyl-1-phenylhydrazine. Ring closure of these intermediates with triethyl orthoacetate or triethyl orthopropionate gave the title compounds in overall yields of 40-60%.     

2-甲基-4-羟基-6-苯基嘧啶和2-甲基-4-羟基-5-溴-6-苯基嘧啶的高效液相色谱法分离测定

采用ODS-C18色谱柱和紫外检测器,对2-甲基-4-羟基-6-苯基嘧啶和2-甲基-4-羟基-5-溴-6-苯基嘧啶的含量进行HPLC分离测定.以甲醇水=4555为流动相,紫外检测波长为237 nm,样品线性范围为0.001～0.1 mg/mL.2-甲基-4-羟基-6-苯基嘧啶的RSD为0.5%;2-甲基-4-羟基-5-溴-6-苯基嘧啶的RSD为1.0%.     

Synthesis of 1,4-dihydro-4-methyl-1-phenyl-5H-1,3,4-benzotriazepin-5-ones

The synthesis of 1,4-dihydro-4-methyl-1-phenyl-5H-1,3,4-benzotriazepin-5-one ( 4a ) and its 8-chloro analog ( 4b ) is described. Attempted synthesis of the 2-methyl analog of 4a from 2-(phenylamino)benzoic acid 1-methylhydrazide ( 10 ) and triethyl orthoaeetate led only to the Schiff base intermediate, 2-(phenylamino)benzoic acid 2-(1-ethoxyethylidene)-1-methylhydrazide ( 11 ). Cyclization of 11 was attempted unsuccessfully with a variety of reagents. The intere?ting reaction products from the treatment of 11 with trifluoroacetic acid are described.     

Synthesis of 1-alkyl-5-phenyl-4(1H)pyrimidinones

1-Alkyl-5-phenyl-4(1H)pyrimidinones are readily synthesized by condensing β-(dimethylamino)-N-[(dimethylamino)methylene] atropamides with methyl or ethyl amine. The latter compounds are prepared from phenylacetamides and dimethylformamide dimethyl acetal.     

1-Phenyl-4(1H)-quinazolinones and 2,3-dihydro-1-phenyl-4(1H)-quinazolinones as potential cholecystokinin receptor ligands

A series of new l-phenyl-4(1H)-quinazolinones and 2,3-dihydro-1-phenyl-4(1H)-quinazolinones were synthesized and tested as cholecystokinin receptor ligands. All the compounds showed moderate affinity and 1-phenyl-4(1H)-quinazolinones resulted more effective towards the cholecystokinin-B receptor, meanwhile the dihydro derivatives were generally more effective towards the cholecystokinin-A receptor.     

Synthesis of 2,3-dihydro-4(1H)-quinoline derivatives

N-Carboxyethyl-N-(3-R-phenyl)-ß-alanines were synthesized by the reaction of m-substituted anilines with acrylic acid; they were cyclized to the corresponding 2,3-dihydro-4(1H)-quinoline derivatives.Translated from Khimiva Geterotsiklicheskikh Soedinenii. No. 4, pp. 523–526, April, 1996.     

Synthesis of 4-Amino-6-phenyl-3-thioxo-2,3-dihydro-1,2,4-triazine-5(4H)-one

Russian Journal of General Chemistry -     

8,9-Methylenedioxy-3,4-dihydro-1,4,5-benzotriazocin-2(1H)-ones

The title compounds are obtained directly on reaction of 6-chloroacetamidopiperonal with substituted phenylhydrazines. Piperonal was used as starting material.     

Synthesis of 6-substituted-4,5-dihydro-3(2H)-pyridazinones

A convenient synthetic method for the pharmaceutically important 6-substituted-4,5-dihydro-3(2H)-pyridazinones is described. The synthetic strategy is based on Δ-soxazolines chemistry which were in turn unmasked by N? O bond cleavage and cyclized to the target compounds.     

Conversion of 6-phenylimino-2H-thiopyran-4-amines to 1-phenyl-2,3-dihydro-4(1H)-pyridinones

Summary 6-Phenylimino-3,6-dihydro-2H-thiopyran-4-amines (1) were converted to 1-phenyl-5,6-dihydropyridine-2(1H)-thiones (3). Those were akylated and hydrolyzed, thus yielding 6-methylthio-1-phenyl-2,3-dihydro-4(1H)-pyridinones (5). Finally, the methylthio group was removed withRaney nickel giving the title compounds6. The relative configurations of the formed diastereoisomeric dihydropyridinones have been investigated by NOE measurements.

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Umwandlung von 6-Phenylimino-2H-thiopyran-4-aminen zu 1-Phenyl-2,3-dihydro-4(1H)-pyridinonen

Zusammenfassung 6-Phenylimino-3,6-dihydro-2H-thiopyran-4-amine (1) wurden in 1-Phenyl-5,6-dihydropyridin-2(1H)-thione (3) umgewandelt. Diese wurden alkyliert und zu 6-Methylthio-1-phenyl-2,3-dihydro-4(1H)-pyridinonen (5) hydrolysiert. Zuletzt gelangte man durch selektives Entfernen der Methylthiogruppe mitRaney-Nickel zu den Titelverbindungen6. Die relativen Konfigurationen der gebildeten diastereomeren Dihydropyridinone wurden durch NOE-Messungen aufgeklärt.