7e-methyl-

Treatment of ethyl 10-methylthio-9-fluoro-3-methyl-2,3-dihydro-7-oxo-7//-pyrido[l,2,3- 7e]-l,4-benzoxazine-6-carboxylate with oxone in aqueous MeOH at 0°C afforded 10-methylsulfonyl derivative (99H(51)1563). Methylthio group in a 7-(4-methylthiophenyl)-5-oxo-2,3-dihydro-5//-pyrido[l,2,3- 7e]-l,4-benzoxazine-3-carboxamide was oxidized to a sulfoxide and a sulfone group (OOMIPl). 

Carboxyl group of (-)-9-fluoro-3-methyl-7-oxo-10-[(3S)-3-(tert-butoxy-carbonylamino)pyrrolidino]-2,3-dihydro-7//-pyrido[l,2,3- 7e]-l,4-benzoxa-zine-6-carboxylic acid was converted into l-nitro-2-oxoethyl group in 45% yield by treatment with l,l -carbonyldiimidazole in boiling CFICI3 for 18h, then with MeN02 in the presence of KOr-Bu for another 18 h (96MI12). 6-(2,2-Diethoxycarbonyl)acetyl derivative formed from the aforementioned 6-carboxylic acid, when it was treated with l,l -carbonyldiimidazole in... 

Ethyl 1 -substituted 7-hydroxy-5-oxo-1,2,3,5-tetrahydropyrido[ 1,2,3-<7e] quinoxaline-6-carboxylates were reacted with A- [3,5-bis(trifluoromethyl)-phenyl]methyl methylamine to yield carboxamides (01MIP12). 

S,4S,5 E,7E)-3-Amino-4-hydroxy-6-methyl-8-(4-bromophenyl)-octa-5,7-dienoic acid [Aboa = Br-Ahmp, Br-Apoa], (2S,3S,8S,9S)-3-Amino-9-methoxy-2,6,8-trimethyl-10-phenyl-deca-4,6-dienoic acid (Adda). 3-Amino-2,4-dimethylpentanoic acid (Admpa). (2S,3R,5S)-3-amino-2,5,9-trihydroxy-10-phenyldecanoic acid (Ahda). j3-Aminoisobutyric acid (jS-AiB). (3S,4S,5E,7E)-3-Amino-4-hydroxy-6-methyl-8-phenylocta-5,7-dienoic acid [Ahmp (Faulkner) or Apoa (Fusetani)]. (2S,3R,5R)-3-Amino-2,5-dihydroxy-8-phenyloctanoic acid (Ahoa). 3-Aminopentanoic acid (Apa /5-Apa). (2R,3R)-3-Amino-2-methylbutanoic add (Amba). 3-Amino-2-methylhexanoic acid (Amha). 3-Amino-2-methyl-7-octynoic add (Amoa, Amoya). 3-Amino-7-octynoic add (Aoya). (2S,3R)-3-Amino-2-methylpentanoic acid (Map). http // www.ncbi.nlm.nih.gov/ Taxonomy/ tax.html... 

Although ethylmethylphenylphosphine oxide was the first tetrahedral phosphorus compound to be resolved only negative results were obtained when attempts were made to resolve methyl(a-naphthyl)phenylarsine oxide (142) by protonation and separation of (-I-)-a-bromocamphor-7E-sulphonate salts, or (o-carboxyphenyl)methylphenyl-arsine oxide (143) or its anhydride 144 after protonation and use of ( —)-brucine or (H-)-morphine . The reversible combination of a tertiary arsine oxide with water was recognized at the outsetand it is this property that is responsible for the racemization ... 

Problem 31.25 In the Doebner-von Miller modification of the Skraup synthesis, aldehydes, ketones, or mixtures of aldehydes and ketones replace the glycerol. If acetaldehyde is used, for example, the product from aniline is 2-methylquinoline(r////w 7/r///7e). (a) Account for its formation, (b) Predict the product if methyl vinyl ketone were used, (c) If a mixture of benzaldehyde and pyi ivic acid, CH3COCOOH, were used. 

A number of methyl- and ethyl-substituted cyclopropanes 7 were brominated under conditions that guaranteed a radical reaction pathway (irradiation at — 78°C in dichloromethane). Methylcyclopropane (7a) underwent exclusive cleavage of the bond next to the substituent to give a quantitative yield of 1,3-dibromobutane (8a). Analogous results were obtained with ethylcyclopropane (7b) and 1,1-dimethylcyclopropane (7c). In 1,2-dimethylcyclopropane (7d) the bond between the substituted and the nonsubstituted carbon atom was cleaved. Higher substituted cyclopropanes 7e and 7f showed a similar reaction course. 

With substituted cycloproparenes, the regioselectivity of the silver(l)-catalyzed and the uncatalyzed reaction was markedly different. Thus, 2-methylbenzocyclopropene (2) reacted with hydrochloric acid to give predominantly w-xylene 3a (47%), but reacted with silver(I) nitrate in the presence of ethanol or aniline to give preferentially o-xylene derivatives 4b,c. 3-Methyl-benzocyclopropene (5a) gave predominantly the w-xylene 7a with hydrochloric acid, but p-xylenes 6b,c in the silver(I)-catalyzed reaction. 3-Chlorobenzocyclopropene (5b) underwent addition of hydrochloric acid to give a mixture of 3- and 4-chlorobenzyl chlorides 6d and 7d, ° but silver(I)-catalyzed methanolysis gave only the 4-chlorobenzyl ether 7e. ... 

The same trend in the electronic effects is observed experimentally for the urazole-bridged 4,5-diazacyclopentane-l,3-diyl triplet diradicals 7 (Table 5), which were chosen to probe for the effect of heteroatom substitution on the D parameter. Substitution of a phenyl by a methyl group in 7d also results in an increased D value in 7g, but is less effective (18%) as seen in the carbocyclic derivatives. These results are in line with the earlier reported [17] D values of iV-phenylurazole-bridged cyclopentene-1,3-diyl triplet diradicals 7a-c (cf. Table 1). As for the carbocyclic diradicals, the electronic substituent effects are reproduced in the diradicals 7e and f not only qualitatively but quantitatively (Table 5). For example, the spin-accepting p-CN substituent in the triplet diradical 7e reduces while the spin-donating... 

---