3-Phenyl Sydnone

Die Beliehtung von Sydnonen licfert 1,2,3-Triazole und/oder 5-Oxo-4,5-dihydro-l, 3,4-oxadiazole. Bei der Beliehtung von 3-Phenyl-sydnon erhalt man als Hauptprodukt 5-Oxo-4-phenyl-4,5-dihydro-1.3 A-oxadiazot -. 

Die Umsetzung von 3-Phenyl-sydnon mit 2,4-Bis-[4-methoxy-pheny ]-1,3,2,4-dithiadiphosph-etan-2,4-bis-sulfid (Lawessons-Reagenz) fiihrt nicht zum erwarteten 3-Phenyl-thiosydnon, son-dern quantitativ zu 1,4-Diphenyl-l,4-dihydro-1,2,4.5-tetrazin56 ... 

Wie die Sydnone lassen sich auch die Sydnon-imine in 1,3-dipolaren Cycloadditionen zu 4,5-Dihydro-pyrazolen und Pyrazolen umsetzen. So erhiilt man aus 3-Phenyl-sydnon-aeyl-iminen durch Reaktion mit Butindisaure-dimethylester 3,4-Dimethoxvcarbonyl-l-phenvl-pyr-azol (30 67%)84 ... 

Satyanarayana K, Rao MNA (1995) Synthesis of 4-[5-(substituted aryl)-4, 5-dihydro-177-pyrazol-3-yl]-3-phenyl-sydnones as antiinflammatory, antiarthritic and analgesic agents. Eur J Med Chem 30 641-645... 

Alkylation ofsydnones. Mesoionic ring systems with exocyclic oxygen atoms ordinarily do not undergo O-alkylation with alkyl halides or sulfates. However, alkylation occurs readily with triethyloxonium fluoroborate. Thus 3-phenyl-sydnone (1) in methylene chloride is alkylated at room temperature to give (2). 

Wird 3-Phenyl-sydnon in Benzol oder 1,4-Dioxan belichtet, so erhalt man ncbon einer Reihe von anderen Produkten 2-Oxo-3-phenyl-2,3-dihydro-1,3,4-oxadiazol l lsl 6 ... 

This procedure is a modification of preparations of 3-phenyl sydnone described earlier.2,3 The dehydration of N-nitroso-Nr phenylglycine has also been effected by the use of thionyl chloride and pyridine in dioxane,4 thionyl chloride in ether,4 trifluoroacetic anhydride in ether,4 and diisopropylcarbodiimide in water or by reaction of the alkali metal salts of N-nitroso-N-phenylglycine with phosgene or benzenesulfonyl chloride in water8 or with acetyl chloride in benzene.4... 

Die Photolyse von 3,4-Diphenyl-sydnon liefert dagegen zu 25% 2,4,5-Triphenyt-l,2,3-tri-azol4 1 4S. Ein ahnliehes Ergebnis wird fiir 3-(4-Methyl-phenyl)-4-phenyl- und 3,4-Bis-[4-methyl-phenyl]-sydnon erhalten. 

Die Beliehtung von 3-tert.-Butyl-4-phenyl-sydnon fiihrt dagegen zur Bildung von 2-Benzoyl-l-tert.-bulyl-4-oxo-3-phenyl-l,2-diazetidin, das in bis zu 68%iger Ausbeute isoliert werden kann49 ... 

Satyanarayana K, RaoMNA (1993) Synthesis of 3-[4-[2, 3-dihydro-2-(substituted aryl)-l, 5-benzothiazepin-4-yl]phenyl]sydnones as potential antiinflammatory agents. Indian J Pharm... 

The earliest example is the addition of benzyne (generated from 4 or by diazotization of anthranilic acid in situ) to N-phenyl sydnone (3-phenyl-l,2,3-oxadiazolium 5-oxide, 138)88 spontaneous loss of carbon dioxide from the intermediate adduct 139 gives 2-phenylindazole (140). Later workers have obtained 140 in higher yield (73%) and the corresponding 2,3-disubstituted indazoles from two other sydnones using benzyne generated by oxidation... 

Auch 3-[2-(1 -Hydroximino-alkyl)-phenyl]-sydnone lagern sich zu lH-Indazolen374,592 um z. B. ... 

Dipoles (i) phenyl azide (carbon tetrachloride. 25 C) - (ii) C-methyl-(V-phenyl-sydnone (p-cymene, I40°C) (iii) picryl azide (chloroform, 25°C) (iv) anhydro-5-hydroxy-2.4-diphenyl-3-methyloxazolium hydroxide, viz. C.C-diphenyl-N-methyl-miinchnone, (benzonitrile. 50°C) (v) benzonitrile oxide (carbon tetrachloride. 25°C) - " . 

Because of their large charge separations and dipole moments, mesionic thiadiazoles are suitable for examination by X-ray photoelectron spectroscopy. Measurements performed on (205) and (206) (as well as on phenyl-sydnone) confirm the view that a betaine structure predominates in the... 

Thieno[3,4-c]pyrazoles.—Cycloaddition of dibenzoylacetylene to N-phenyl-sydnone (78) afforded the pyrazole (79), which, when thionated (P2Ss Pyridine), gave in high yield the stable triphenylthieno[3,4-c]pyrazole (80), the first reported member of this class." Compound (80) enters into cycloaddition reactions, notably with dibenzoylacetylene, with loss of sulphur, giving the diketone (81). Thionation of compound (81) gives, in high yield, the stable blue-black quadricovalent species (82). The mass spectra of... 

Enamines and enolate anions react with benzofuroxan to give quinoxaline di-A -oxides (Scheme 38) (69AHC(10)1). Sydnones (274) with phenyl isocyanate give 1,2,4-triazoles (275) (76AHC(19)l), and from (276) the intermediate adduct (277) can be isolated (73JA8452). This is one of the few instances in which such primary cycloadducts have been isolated in the oxazole series of mesoionic compounds. 

Sydnone, 3-methyl-conductance, 6, 371 dielectric constants, 6, 368 dipole moments, 6, 368 Sydnone, 3-methyl-4-phenyl-nitration, 6, 372... 

Sydnone, 3-p-nitrophenyl-4-phenyl-mass spectra, 6, 370 Sydnone, 3-phenyl-acetylation, 5, 58 6, 373 carbonylation, 6, 373 dipole moments, 6, 368 nitration, 6, 372 reduction, 6, 371 Vilsmeier reaction, 6, 373 Sydnone, 4-phenyl-3-p-tolyl-photolysis, 6, 374 Sydnone, 3-(3-pyridyl)-photolysis, 6, 375 Sydnone, 3-p-tolyl-dipole moments, 6, 368 Sydnones... 

The compound 7-(4-chloro-benzyl)-2-(4-chloro-phenyl)-3,8a-dihydro-pyridazino[4,3-( ][l,3,4] thiadiazin-8-one 42 has been reported to be active against Bacillus Escherchia coli, Staphylococcus aureus, and Pseudomonas aeruginosa by a serial dilution method <2001IJB475>. Triazino-thiadiazines 24f, 25b, 25c, and 25f <2002IJH287> have been reported to be active against S. aureus-, sydnone derivatives of triazino-thiadiazine 24f <2002IJH287> are more reactive than coumarin derivatives. 

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