JV-methylation

Piperidine, l-(2-hydroxythiobenzoyI)-neutron diffraction, 2, 116 Piperidine, 4-hydroxy-2,2,6-trimethyI-as local anaesthetic, 1, 179 Piperidine, JV-methoxycarbonyl-electrolytic oxidation, 2, 374 Piperidine, 2-methyl-synthesis, 2, 524 Piperidine, 3-methyI-mass spectrometry, 2, 130 Piperidine, C-methyl-NMR, 2, 160 Piperidine, JV-methyl- C chemical shifts, 2, 15 catalyst... 

Pteridine-7-carboxamide, JV-methyl-6-oxo-synthesis, 3, 310 Pteridine-4-carboxamides properties, 3, 276... 

Forsyth et al. found that gelsemicine contains three active hydrogen atoms (Zerewitinov determination), yields a non-basic, monobenzoyl derivative, m.p. 232°, and behaves as a secondary base giving JV-methyl-gelsemicine hydriodide, m.p. 227°, on treatment with methyl iodide. It does not react with either hydroxylamine or 2 4-dinitrophenylhydrazine. On hydrogenation in dry acetic acid in presence of Adams s platinic oxide catalyst it absorbs three molecules of hydrogen. 

Reaction of 1,4-diazocinediones with methylating agents leads to different products depending on the conditions. With dimethyl sulfate, the annulated derivative 6 gives JV-methylation selectively 7 however, on reaction with diazomethane, a mixture of the O- and iV-methylated products is obtained.9... 

Methylation of the 6,7-dimethyl derivative of 133 with methyl iodide in sodium hydroxide or sodium ethoxide gave two S,N-dimethyl derivatives, whereas in sodamide or ammonia, only the 5-methyl derivative was obtained. Methylation with diazomethane gave four methyl derivatives and with methyl chloride two di-jV-methyl and one 5,/V-dimethy] derivative were obtained (80H1139). Methylation of 153, obtained from 152, gave 4-methyl-3-methylthio-triazinoindole 155, whose hydrolysis or oxidation gave 154 (76T1735). On the other hand, methylation of 156 gave methiodide... 

C20H23NO4S 80138-94-9) see Levocabastine tranx-3-methyl-l-[(4-methylphenyl)sulfonyll-4-phenyl-4-piperidinecarboxylic acid phenylmethyl ester (C27H29NO4S 104907-69-9) see Levocabastine ( )-JV-methyl-2-[3-(l-methyl-4-piperidinyl)-l//-indol-S-yllethenesulfonamide... 

There have been no reports of complexes of " JV-substituted thiosemicarbazones derived from 2-formylpyridine, but 2-acetylpyridine JV-methyl-thiosemicarbazone, 3a, formed [Fe(3a-H)2]C104 and [Fe(3a-H)2]FeCl4 [117]. The nature of these two species was established by partial elemental analyses, molar conductivities, magnetic moments, electronic, infrared, mass and electron spin resonance spectra. A crystal structure of a related selenosemicarbazone complex confirmed the presence of a distorted octahedral iron(III) cation coordinated by two deprotonated anions so that each ligand is essentially planar and the azomethine nitrogens are trans to each other the pyridyl nitrogen and selenium donors are both cis. 

Methyl-3-oxo-3,4-dihydro-6-quinoxalinesulfonamide jV-Methyl-3-oxo-4-phenyl-3,4-dihydro-2-quinoxalinecarboxamide... 

Still more crowded amides were prepared with jV-methyl-2,6-xylidine as the amino component 8 1 or with 2,4,6-trimethoxyaniline [28b]... 

A major study on 13C-NMR spectroscopy of hasubanan alkaloids was carried out by Matsui et al. (5) (Table III). They proposed assignments of all carbon atoms including the direct and long-range hetero coupling. The C-9 and JV-methyl carbons of hasubanan alkaloids reveal shifts of 6 and 20 ppm higher frequency than those reported for morphinan alkaloids (9). On the other hand, the iV-methyl carbons of hasubanans exhibit a lower frequency shift of 10 ppm relative to those of hasubanalactam-type alkaloids (5). These results have been utilized for structure elucidation in later works (4,7,10-12). 

Oxostephasunoline (4) was isolated from the roots of Stephania japonica(4). The UV spectrum of oxostephasunoline (4) showed an absorption maximum at 286 nm, and the IR spectrum depicted bands at 3550,3500, and 1670 cm, indicating the presence of a hydroxyl group and a y-lactam. The mass spectrum (Table VI) exhibited the most abundant ion peak at m/z 258, and the H-NMR spectrum (Table II) revealed the presence of three methoxyl and one N-methyl group. The downfield shift (53.06) of the JV-methyl resonance indicated that oxostephasunoline (4) was a y-lactam, which was further supported by the IR band at 1670 cm 1, significant features of the mass spectrum (Table VI), and the 13C-NMR spectrum (Table III). On exhaustive H-NMR analysis similar to the case of stephasunoline (17), the structure of oxostephasunoline (4) including the stereochemistry was practically proved (4). 

Stephadiamine (16) was isolated as a minor component from the ethanolic extract of the whole plant of Stephania japonica collected in Taiwan (6). The IR spectrum of stephadiamine (16) exhibited bands at 3375 (NH2) and 1720 cm 1 (5-lactone), and the H-NMR spectrum (Table II) showed the presence of one JV-methyl and two methoxyl groups. Its mass spectrum revealed a base ion peak at m/z 243 of stephamiersine-type cleavage (Table V) (6). 

Fagg, G.E., Phencyclidine and related drugs bind to the activated JV-methyl-D-aspartate receptor-channels complex in rat membranes, Neurosci. Lett., 76, 221, 1987. 

Haracz J., Belanger S., MacDonall J., Sircar R. Antagonists of JV-methyl-D-aspartate receptors partially prevent the development of cocaine sensitization. Life Sci. 57 2347, 1995. 

Itzhak Y., Stein I. Sensitization to the toxic effects of cocaine in mice is associated with regulation of jV-methyl-D-aspartate receptors in the cortex. J. Pharmacol. Exp. Ther. 262 464, 1992. 

Reaction of porphyrins with nitrones has also been studied and the results obtained showed that this is a versatile approach leading to the synthesis of isoxazolidine fused-chlorins (Scheme 26). For instance, chlorin 74 was successfully prepared from the reaction of the jV-methylnitrone, generated in situ from JV-methyl hydroxylamine and paraformaldehyde, with porphyrin Id . It is important to note that bis-addition also took place, yielding exclusively bacteriochlorin type derivatives 76 and 77 (Figure 6). This result contrasts with those obtained in 1,3-DC reactions with azomethinic ylides where isobacteriochlorins were obtained preferentially. 

Analogously, the mesoionic jV-methyl thiazol-5-ones and l,3-dithiol-4-ones afforded A-methyl-4-pyridones and thiapyran-4-ones when reacting with diphenyl cyclopropenone and its thione261. Benzonitrile oxide apparently gives a 1,3-dipolar cycloaddition to the C=0 group of diphenyl cyclopropenone rationalizing the formation of triphenyl-l,3-oxazin-6-one 41626i ... 

ENDOCYCLIC ENAMINE SYNTHESIS JV-METHYL- 2- PHENYL- A -TETRA-HYDROPYRIDINE, 54, 93 Enol acetates, acylation of,... 

In the reaction of A-methylaniline, ethyl orthoformate, and Meldrum s acid (421) in the presence of p-toluenesulfonic acid monohydrate at 100°C for 2 hr, then for 3 days at ambient temperature, (jV-methyl-TV-phenylamino)methylenemalonate (443) was obtained in 41% yield (69BRP1147759). 

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