5-Hydrazino-3-phenyl

Hydrazino-3-phenyl[l,2,4]oxadiazole (123) and -thiadiazole (124) react with formic acid to give 3-phenyl[l,2,4]triazolo[4,3-rf][l,2,4]oxadiazole (125) and -thiadiazole (126), respectively (Equation (32)) <91MI 807-05>. 

Nitro-4-phenoxy-benzol- XII/1, 380 (4-Nitro-pheny]-hydrazino)-phenyl-methan- -... 

Eine Erweiterung der Reaktionsmoglichkeiten stellt der Einsatz von Natrium-hydra-zid/Hydrazin dar, das 1-Aryl-l -alkene zu den entsprechenden Aryl-alkanen reduziert. So erhalt man bei der Reduktion von rrans-Stilben in Benzol 96% d.Th. 1,2-Diphenyl-athan6 7, als Nebenprodukt fallt /-Phenyl-2-(2-hydrazino-phenyl)-dthan1 an. 

Purines, N-alkyl-N-phenyl-synthesis, 5, 576 Purines, alkylthio-hydrolysis, 5, 560 Mannich reaction, 5, 536 Michael addition reactions, 5, 536 Purines, S-alkylthio-hydrolysis, 5, 560 Purines, amino-alkylation, 5, 530, 551 IR spectra, 5, 518 reactions, 5, 551-553 with diazonium ions, 5, 538 reduction, 5, 541 UV spectra, 5, 517 Purines, N-amino-synthesis, 5, 595 Purines, aminohydroxy-hydrogenation, 5, 555 reactions, 5, 555 Purines, aminooxo-reactions, 5, 557 thiation, 5, 557 Purines, bromo-synthesis, 5, 557 Purines, chloro-synthesis, 5, 573 Purines, cyano-reactions, 5, 550 Purines, dialkoxy-rearrangement, 5, 558 Purines, diazoreactions, 5, 96 Purines, dioxo-alkylation, 5, 532 Purines, N-glycosyl-, 5, 536 Purines, halo-N-alkylation, 5, 529 hydrogenolysis, 5, 562 reactions, 5, 561-562, 564 with alkoxides, 5, 563 synthesis, 5, 556 Purines, hydrazino-reactions, 5, 553 Purines, hydroxyamino-reactions, 5, 556 Purines, 8-lithiotrimethylsilyl-nucleosides alkylation, 5, 537 Purines, N-methyl-magnetic circular dichroism, 5, 523 Purines, methylthio-bromination, 5, 559 Purines, nitro-reactions, 5, 550, 551 Purines, oxo-alkylation, 5, 532 amination, 5, 557 dipole moments, 5, 522 H NMR, 5, 512 pJfa, 5, 524 reactions, 5, 556-557 with diazonium ions, 5, 538 reduction, 5, 541 thiation, 5, 557 Purines, oxohydro-IR spectra, 5, 518 Purines, selenoxo-synthesis, 5, 597 Purines, thio-acylation, 5, 559 alkylation, 5, 559 Purines, thioxo-acetylation, 5, 559... 

The methoxy group is replaced in the reaction of 3-methoxy-5-phenyl-1,2,4-triazine 1-oxide 46 with ammonia, resulting in 3-amino-5-phenyl-1,2,4-triazine 1-oxide 47. The treatment of 3-methoxy-1,2,4-triazine 1-oxide 20 with hydrazine leads to 3-hydrazino-1,2,4-triazine 1-oxide 48 (71JOC787). 

The free selenazole hydrazines are solids, sometimes well crystallized compounds. They show the typical properties of hydrazines. Thus they reduce Fehling s solution on warming and liberate silver, even in the cold, from ammoniacal silver nitrate solution. Further, they react with carbonyl compounds for example, benzylidene hydrazones are formed with benzaldehyde. These are identical with the hydrazones formed by direct condensation from benzaldehyde selenosemicarbazone and the corresponding a-halogenocarbonyl compound. 2-Hydrazino-4-phenylselenazole has also been reacted with acetophenone. The 2-a-methylbenzylidenehydrazone of 4-phenyl-selenazole (2, K = CJl, R" = H, R" = NH—N CMe-aH ) forms golden yellow plates mp 171°C. ... 

Hydrazone of 1 -hydrazino-1 -hydroxy-4-phenyl-1,2-dihydro-3//-pyrido [l,2-c]pyrimidin-3-one was patented as cross-linkers for making physiologically compatible and H2O insoluble hydrazine or hydrazono compounds (97JAP(K)97/59303). 

Cyclization of 8-hydrazinO 3-phenyl-l-azaazulenes 69 with triethyl orthoformate gave 4,5-triazabenz[c(f]azulene derivative 70 which was easily hydrolyzed on silica gel and gave (2-chloro-8-imino-3-phenyl-l-aza-l,8-dihydoazulen-l-yl) formaldehyde oxime (87H767) (Scheme 17). 

Benzoyl-hydrazino)-117 2-Benzoyloxy-2-phenyl- 630 2-Benzoyloxy-2-phenyl- -methylester 630 2-Benzylamino- -athylester 2/2... 

Oxo-9,10-dihydro- 654 l-Oxo-l,2,3,4-tetrahydro- 765 4-Oxo-l,2,3,4-tetrahydro- 766 9-Phenylazo- 482 9-(2-Phenyl-hydrazino)-... 

A series of novel l-substituted-4-phenyl-l,2,3-triazolo(4,3-a)quinazolin-5(4H)-ones 1 were synthesized by the cyclization of 2-hydrazino-3-phenyl-quinazolin-4(3H) 2 with various one carbon donors. The starting material 2-hydrazino-3-phenylquinazolin-4(3H)-one 2, was synthesized from aniline 7 by a novel innovative route. When tested for their in vivo Hi-antihistaminic activity on conscious guinea pigs all the test compounds protected the animals from histamine-induced bronchospasm significantly, whereas the compound l-methyl-4-phenyl-l,2,3-triazolo(4,3-a)quinazolin-5(4H)-one lb (percentage protection 70.7%) was found to be equipotent with the reference standard chlorpheniramine maleate (percentage protection 71%). These compounds show negligible sedation (5%) when compared to the reference standard (26%). Hence they could serve as prototype molecules for future development [1,4,5]. 

The parent heterocycle of pyrido[2,3-e][l,2,4]triazine and its phenyl derivative 39 were prepared (89JHC475) by cyclization with polyphos-phoric acid of 3-acyIhydrazino-2-aminopyridines 36, obtained by reduction of the corresponding 3-acylhydrazino-2-nitropyridines 35. Compounds 35 were obtained from 3-fluoro-2-nitropyridine 34 either by reaction with benzoylhydrazine or by reaction with hydrazine and subsequent for-mylation of the initially formed 3-hydrazino-2-nitropyridine 38. Attempts to prepare 38 from 3-chloro-2-nitropyridine gave 2-hydrazino-3-chloropyridine 37. These results could be explained by semiempirical calculations (CNDO and MNDO calculations). 

This ring system is represented by tricyclic ring system 533 (76JHC1249). Reaction of 3-hydrazino[l,2,4]triazin-5-ones 531 with 3-imi-nobutyronitrile afforded 6-methyl- (or phenyl-) 3-[3-methyl-5-aminopyra-zolyl]-2,5-dihydro[l,2,4]triazin-5-ones 532A, which may exist in tautomeric form 532B. Its reaction with diethoxymethyl acetate (DEMA) or ortho-esters afforded the tricyclic compounds 533. 

Cyclocondensation of 754 with phenacyl bromide gave (86JHC721) 3-phenyl-7,7,11 -trimethyl-8//-benzopyrano[4,3-e]imidazo[ 1,2-b] [1,2,4]-triazine 755. Cyclization of the 3-hydrazino derivative 756, with formic acid gave 757. Compounds 754 and 756 were prepared by reaction of the triazinobenzopyrane 753 with phosphorus oxychloride, followed by amination or hydrazinolysis (86JHC721). 

MethyM-cthoxycarbonyl-5-bcnzoyl-hydrazino-l //-pyrazole 274, prepared by reacting benzoyl chloride and 3-methyM-cthoxycarbonyl-5-bcnzoyl-hydrazino-l //-pyrazole hydrochloride 273, in the presence of pyridine in acetonitrile, has been cyclized with phosphoryl chloride in benzene or toluene to give 7-ethoxycarbonyl-6-methyl-3-phenyl-l //-pyrazolo[5,l -/ 1,2,4 triazolc 55. This compound has been also synthesized through cyclization of... 

The reaction of 2-anilino-l,4-naphthoquinone 374 with benzoylacetic acid hydrazide gives 3-hydrazino-pyrazolyl derivative 375, that is acetylated to produce 5-[[l,4-dihydro-l,4-dioxo-3-(phenylamino)-2-naphthalenyl]sulfonyl]-3-methyl-6-phenyl-5/7-pyrazolo[5,l-c][l,2,4]triazole 51. This latter derivative is also obtained in 51% yield from reaction of 374 with benzoylacetic acid hydrazide in the presence of a mixture of acetic acid-sodium acetate <2004PS(179)1907> (Scheme 39). 

Quite similarly, the reaction product obtained from 2-benzylthio-3-phenylquinazolin-4(3H)-thione and hydrazine should be assigned the structure 2-anilino-3-aminoquinazoline-4(3//)-hydrazone instead of the reported 2-hydrazino-3-phenyl quinazoline-4(3//)hydrazone (Scheme III.23) (70IJC1055). 

Similarly to the rearrangement observed with l-aryl-5-hydrazino-l, 2,3-triazole (see Section IV,B,l,a), 3-phenyl-2-hydrazonothiazoline (20) is rearranged by acid at room temperature into 3-amino-2-(phenylimino) thiazoline (21) (Scheme IV.12) (61LA66). 

Scheme 49 Synthesis of furanose-fused C-glycosyl a-hydrazino lactones from phenyl-1-seleno glycosyl donors...

Aus Anilino-guanidin werden mit a -Brom-acetophenonen 4-Aryl-2-(2-phenyl-hydrazino)-imidazole und nicht die ebenfalls als Produkte denkbaren 2-Amino-l-anilino-imidazole erhalten106 (s.a. Bd.X/2, S. 739) ... 

Aus [l-Methyl-2-phenyl-2-(2-phenyl-hydrazino)-ethenyIamino]-malonsaure-methylester-nitril wird durch Kochen in Methanol in 68% Ausbeute l-Anilino-2-methoxycarbonyl-4-methyl-5-phenyl-imidazol erhalten328 ... 

Zur photochemischen Geriistumlagerung von Methyl-imidazolen s. Bd.IV/5a, S.562. 2-(2-Aryl-hydrazino)-imidazole unterliegen in konz. Salzsaure einer Benzidin-Umlagerung zu 2-Amino-4(5)-(4-amino-phenyl)-imidazolen1214,1215 (Bd.Xl/1, S. 847). 

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