4-Benzoylamino-4-

Phenyliinino-3-benzoylamino-4-thiazoline (412) rearranges in basic medium to 2-anilino-5-pheny -l,3,4-oxadiazole (413) (Scheme 236) 730). 

C5H9NO 10431-98-8) see Nefazodone hydrochloride ( )-ethyl 2-oxo-3-benzoylamino-3-phenylpropionate (C H,7N04 153433-79-5) see Paclitaxel ethyl 3-oxocaproatc... 

A few examples, illustrating the principle of this type of degenerate rearrangement, are the thermo-induced equilibrium shift of 3-benzoylamino-5-methyl-l,2,4-oxadiazole into 3-acetylamino-5-phenyl-l,2,4-oxadiazole and the isomerization of 5-benzoyl-methylfuroxan oxime into 4-[a-nitroethyl]-3-phenylfurazan (82G181) (Scheme 1.8). They are extensively discussed in Chapter IV. 

One of the earlier examples of a degenerate ring transformation involving the participation of a three-atom side chain is the interconversion of the isomers 3-benzoylamino-5-methyl-l,2,4-oxadiazole (133, X = H) and 3-acetylamino-5-phenyl-l,2,4-oxadiazole (134, X = H) (Scheme IV.51) (75JHC985 89H(29)737). Heating each of these compounds at 181°C furnished an identical equilibrium mixture of isomers, in which mixture isomer 134 (X = H) is predominant (X134/133 at 181°C is about 6.4). These data indicate that the conversion of isomer 133 (X = H) into 134 (X = H) is dri-... 

No loss of optical purity was observed in the mild acidic hydrolysis of the enantiomerically pure 6-alkoxy -phenyl-5,6-dihydro-4/7-l,3-oxazine 132, which resulted in formation of (R)-3-benzoylamino-3-phenylpropanal 133 in excellent yield (Scheme 20). Hydrolysis of the analogous tetrahydro-l,3-oxazin-2-one 134 to 133 required a stronger acidic medium and took place only in poor yield, but without any decrease in the optical purity <20000L585, 2003JOC4338, 2004TL9589>. 

The ring-opening reactions of l,3-oxazin-6-ones with nucleophiles or electrophiles both result in / -amino acid derivatives. Methanolysis of 2-phenyl-4,5-dihydro-l,3-oxazin-6-one 206 under very mild conditions gave methyl 3-(benzoylamino)propionate 207 (Equation 19) <20030L1575>. 

Similarly, reaction of 2-dimethylaminomethylene-3-oxoalkanoates or 2-di-methylaminomethylene-1,3-cyclohexanediones with 2-phenyl-5(4/7)-oxazolone 146, generated in situ from hippuric acid, affords 6-substituted 3-(benzoyl-amino)-2-oxo-2//-pyran-5-carboxylates 204 and 3-(benzoylamino)-7,8-dihydro-2//-l-benzopyran-2,5(6//)-diones 206, respectively. These compounds showed strong local anesthetic activity (Scheme 7.62). ... 

Analog reagiert 4-Amino-3-phenyl-furazan mit Chrom(VI)-oxid in Eisessig (Bis-[4-phenyl-furazan-3-yl -diazen)265 3-Benzoylamino-4-amino-furazan laBt sich mit Brom/Natronlauge zur Azo-Verbindung (Bis-[4-benzoylamino-furazan-3-yl]-diazen) umsetzen263. 

Clarke et al. reported that 2-phenyl-4-[(2-pyridylamino)methylene]-5-oxazolinone 178 (R = R1 = H) isomerized to 3-benzoylamino-4//-pyrido[l, 2-a]pyrimidin-4-one 180 (R = R1 = H) when it stood in ethanolic sodium ethoxide in room temperature (49MI1). Later it was pointed out... 

S)-Methyl-3-(benzoylamino)butanoate (S)-72 is also available by enzymatic resolution with pig liver esterase. Alkylation and amination were run on the racemic compounds. One example of electrophilic amination is reported starting from rac-72 which is doubly deprotonated with LDA at low temperature (-60 °C to -45 °C). The enolate intermediate adopts an (E) configuration. After treatment at -70 °C with DTBAD (1.2 equiv.) in THF, the product 73 is obtained with 96% yield and an excellent diastereoselectivity de > 99 % in favor of the anri-diastereomer (Scheme 34). The absolute configuration of the created stereogenic center was assigned by chemical correlation with the known anti-2,3-diaminobutanoic acid. 

Benzyl 3-Benzoylamino-4,6-0-benzylidene-2-fluoro-2,3-dideoxy- -D-aItropyranoside (22) Typical Procedure for Ring Opening of A/.iridines with Tetrabutylammonium Fluoride " ... 

The quinazoline ring of 1,2,4-triazolo[4,3-a]quinazoline 348 was formed (62TL1193) by the dehydrative cyclization of 3-benzoylamino-4,5-diphenyl-1,2,4-triazole (347). Alternatively, 1,2,4-triazolo[4,3-a]-quinazolines were prepared by assembling the fused 1,2,4-triazole ring onto the quinazoline nucleus when 2-hydrazinoquinazolines (e.g. 349) were cyclized with formic acid or acetic anhydride to give (86JHC833) angular l,2,4-triazolo[4,3-a]quinazolinones 350 in addition to linear 1,2,4-triazolo[3,4-/>]quinazolinones 351. 

These compounds were obtained (70S433) by cyclization of 2-hydrazinoazepines such as 2-hydrazino-3,4,5,6,7-pentahydroazepine (525) with A -dichloromethylene benzamide to give 3-benzoylamino-l,2,4-triazolo[4,3-a]5,6,7,8,9-pentahydroazepine (526). Reaction of methyl chloroformate, phosgene, or thiophosgene with the 3,4,5,6,7-penta-hydroazepin-2-one arylhydrazones (527) afforded (80USP4213773) the 3-0X0- or 3-thioxo-5,6,7,8,9-pentahydro-l,2,4-triazolo[4,3-a]azepines (528). 

Die Umlagerung von 3-[a-(2-Methyl-2-phenyl-hydrazono)-benzyl]-5-phenyl-l,2,4-oxadiazolin siedendem Benzol fiihrt zu 3-Benzoylamino- 1-methyl-lH-indazol 25 (70% Schmp. 188 190°), wobei in Analogie zu ahnlichen Umlagerungen ein Triazol-Intermediat postuliert wird, das nach Eliminierung von Bcnzonitril iiber ein Carbodiimid-lntermcdiat zum Indazol cyclisiert625. 

Bcnzoylamino-1-benzyl- 804 3-Benzoylamino-l-cthyl- 804 3-Benzoylamino-l-methyl- 792... 

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