Methyl rings

Naphtho[2,1 -/]pyrido[2,1 -h][ 1,3]thiazepinium perchlorate, 7-methyl-ring contraction, 2, 558 Naphthopyrylium salts synthesis, 3, 870, 873... 

Elementary considerations indicate that with appropriate substitutions some of the reactions mentioned above can be eliminated. Indeed, when 5-methyl-2-vinyl-furan was used, no alkylation was observed, the positions C-3 and C-4 being rather unreactive16, and the polymer was a mixture of linear chains with polyunsaturations and linear saturated chains, i.e. only structures like 21, 23 and 26 were present, with a 5-methyl ring instead of the 5-unsubstituted one. When 2-isopropenylfuran was used, no hydride transfer took place since this requires a hydrogen atom in the a-position to the ring, which this monomer does not have the polymers were white and gave electronic spectra transparent down to 280 nm. Alkylation at C-5, how-... 

Metallocenes with substituted cyclopentadienyl rings. Metallocenes with methylated rings were among the first heavy alkaline earth metallocenes to be structurally characterized, but many other substituents have been incorporated into bis(cyclopentadienyl) complexes. Under this classification are included compounds with indenyl ligands, which in... 

Diaminobenzene-IV,IV,IV, IV -tetraacetate (248, 250) and chloro- and methyl-ring-substituted derivatives (248)... 

H- l-Benzazepine-2,5-dione, 3-amino-4-methyl-ring contraction, 7, 527 1H-1 -Benzazepine-2,5-dione, 3-hydroxy-chlorination, 7, 517... 

Based on the peak areas from the GC analysis, HFBT accounted for 58% of the two products recovered and methyl-HFBT accounted for 42% (Fedorak and Payzant, unpublished data). This proportion was quite different than that of the added substrates suggesting that the methyl-substituted compound was less susceptible to the biotransformation or that both the methylated ring and the nonmethylated benzene ring of 4-methyldibenzothiophene were susceptible to cleavage yielding a mixture of HFBT and methyl-HFBT for this one substrate. None-the-less, this preliminary study suggested that microbial metabolism of isomers of Ci-dibenzothiophene should yield the isomers of methyl-HFBT. 

Benzimidazoles, 2,3-dihydro-, by Nu addition at C-2, 56, 203 Benzimidazole, 2-fluoro-, 59, 272 Benzimidazole, 1-methyl-, ring expansion to chloroquinoxalines, 59, 305 Benzimidazole, l-methyl-2-(5 -methyl-2 -thienyl)-, bromination, 57, 319 Benzimidazole 3-oxides, chloro-deoxygenation, 59, 270 Benzimidazoles, 2-perfluoroalkyl-, 60, 25 Benzimidazoles, 2-(l-pyridinio)-, 60, 204 Benzimidazoles, 2-(2-pyridinioethyl)-, elimination reactions, 60, 246 Benzimidazoles, tetrafluoro-, 59, 14 Benzimidazole-2-carboxylic ester 3-oxide, 7-nitro-5-trifluoromethyl-, 60, 17 Benzimidazolium salts, l-amino-3-alkyl-, reaction with activated acetylenes, 56, 138... 

H-Azepine, 2-(o-hydroxyphenyl)-synthesis, 7, 538 3H-Azepine, methyl- H NMR, 7, 495 3H-Azepine, 3-methyl-ring inversion barrier, 7, 14 3H-Azepine, 2-methylene-isomerization, 7, 505 3H-Azepine, 7-(N-phthalimido) synthesis, 7, 538 4H-Azepine, 4,5-dihydro-cyclization, 7, 524... 

Aromatic Glucuronic acid conjugation sulphate conjugation methylation ring hydroxylation... 

The reaction of a secondary amine cannot, of course, lead to a pyridine, however in pyrylinms carrying an a-methyl, ring closure to an arene can occnr, this time via an enamine. ... 

If the 2-position bears hydrogen or methyl, ring-opening reactions of 4//-pyrido[3,4-r/] [1,3]oxazin-4-ones with ammonia, hydroxylamine, hydrazine, or aniline to give the 3-(acyl-amino)pyridine-4-carboxamides are directly followed by ring closure to yield the corresponding pyrido[3,4-ri]pyrimidin-4(3//)-ones.463,484... 

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