L-Benzyl-4-hydroxy-4-

Allylische Silane gehen mit Benzylamin und waBrigem Formaldehyd in Gegenwart von Trifluoressigsaure eine Cyclokondensation ein unter Bildung von z. B. l-Benzyl-4-hydroxy-piperidin, 2-Renzyl-4a-hydroxy-cis-decahydro-isochinolin bzw. l-Benzyl-4-hydroxy-4-( 2-hydroxy-ethyl)-piperidin2. 

Pyrrole-2-carboxamide, N,N-dimethyl-conformation, 4, 194 Pyrrole-3-carboxamide, N,N-dimethyl-conformation, 4, 194 Pyrrolecarboxamides synthesis, 4, 242 Pyrrole-2-carboxamides synthesis, 4, 148, 360 Pyrrolecarboxylhydrazides Curtius degradation, 4, 362 Pyrrole-2-carboxylic acid, l-benzyl-3-hydroxy-ethyl ester... 

Some of the l-aryl-5-hydroxy-A2-l,2,3-triazolines with two different substituent groups at C-4 exist in solution as a mixture of the diastereomers they are readily interconvertible via a ketotriazene (59-62).259 The compositions of the equilibrium mixtures for a number of 1-methyl- and l-benzyl-5-hydroxy-A2-l,2,3-triazolines in solution were determined by NMR spectroscopy. The 8 values of the methyl groups at C-4 fall into two regions, namely at 81.41-1.57 or 1.05-1.21. They can be oriented either cis or trans relative to the hydroxy group at C-5. The compounds with bulky substituents at C-5 exist only in one form in which the bulky C-5 group is trans to the methyl group at C-4. The... 

Sakamoto et al. found that. S -phenyl Y-benzoylfomiyl-A-tp-tolyljthiocarbamatc 54 crystallized in chiral space group P2i.[33] Photolysis of the chiral crystals in the solid-state gave optically active l-benzyl-4-phenyl-4-phenylthiooxazolidine-2,4-dione (55, 16% chemical yield, 21% ee) and cw-3,4-diphenyl-3-hydroxy-l-(thiophenylcarbonyl)-azetidin-2-one (56, 18% chemical yield, 23% ee) in 62 % conversion yield. Better optical purities were observed at low conversion (in 17% cov.), 46% ee for 55, and 32% ee for 56, respectively. 

Acetyl-l-benzyl-5-hydroxy-3,4,7,8-tetrahydro-l, 7-naphthyridin-2(l //)-one (10) underwent catalytic dehydrogenation and rearrangement to give 5-acetoxy-3,4-dillydro-l,7-naphthyridin-2(l//)-one (11) (Pd/C, xylene, 135°C, 30 h 45%).1272... 

Benzoyloxy-benzol- XII/1, 369 Benzyloxymethan- -diethylester XII/1, 452 1-Benzoyloxy- l-methyl-ethan- XII/1, 376 Bcnzylamino-(4-chlor-phenyl)-methan- E2, 304 l-Benzylamtno-2-methyl-propan- E2, 304 Benzylamino-phenyl-methan- E2. 300, 304 4-Benzyl-bcnzol- -dichlorid XII/1, 348, 388, 392 l-Benzyl-2-hydroxy-ethan- -bis-[2-chlor-ethyI-... 

I-Benzyl-4,5-dimethyl-6-hydroxy-2-phenyl-1,6-dihydro- - 1-oxid E2, 88 l-Benzyl-4,5-dimethyl-2-phenyl- 1,6-dihydro- -1-sulfid E2, 88... 

R,4R)-4-Benzyl-l-[2-(4-hydroxy-benzenesulfonyl)-ethyl]-piperidin-3-ol was also prepared by the author and is described. 

Pyrazolidin 2-Benzyl-4-hydroxy-l-methyl- El6a, 554 (Hydrazin-1,2-Cycloalkyl.)... 

Carboxylation of the potassium salt of 3-hydroxy-6-methylpyridine (145) gave the picolinic acid 146(84MI16). The Hammick condensation reaction of picolinic acid with benzaldehyde has been studied with regard to the effect of solvent, temperature, and molar ratio of reactants (85MI5). Benzoyl chloride, or benzaldehyde, and l-benzyl-4,6-diphenylpyridinium-2-carboxylate afford 2-benzoyl-4,6-diphenylpyridine (85JCS(P1)2167). Sulfur and 1,4,6-triaryl-pyridinium-2-carboxylates 147 in xylene at 140°C give the corresponding pyridine-2-thiones 148(838149). 

Among procedures for the synthesis of 1,7-naphthyridines, four-component condensation of l-benzyl-3-hydroxy-5-piperidone 101 with 2,3-dichloro-6-fluorobenz-aldehyde, acetoacetic esters and ammonium acetate giving rise to 1,4,5,6,7-hexahydro-l,7-naphtyridin-5-one-3-carboxylic esters 102 attracts attention due to its simplicity. The compounds 102 and their N-debenzylation products 103 exhibit hypotensive activity (1985USP4596873, 1985USP4618678). 

The reaction of 1,3-disubstituted perhydropyrido[l,2-c][l,3]oxazines (69) and 7-(benzothiazol-l-yl)-6,7-dihydro-17/,3//,5//-pyrido[3,2,l-iy][3,l]benz-oxazine with Grignard reagents led to 2-(/V-substituted 2-piperidyl)ethanols (70) (50JA358 58CLY2081) and l-benzyl-4-(benzotriazol-l-yl)-8-hydroxy-methyl-l,2,3,4-tetrahydroquinoline (95JOC3993), respectively. 

In formal ahnlicher Weise bildct sich aus 2-[a-(4,5-Dimethoxycarbonyl-l,3-dithiol-2-yliden)-benzyl]-4-hydroxy-5-phenyl-l,3-thiazol zu 12% 2-(a.-Cyan-henzyliden)-4,5-dimethoxycarbonyl- 1,3-dithiol899. 

H-(j>yrido[2,3-c pyrazol)2l03 2105,2109 R = CH2—csh5, l-Benzyl-6-hydroxy-4-methyl-... ... 

Mit Benzylchlorid reagiert 3-Hydroxy-lH-indazolebenfalls zunachst unter N-Benzylierung zu l-Benzyl-3-hydroxy-lH-indazol (45%), das mit weiterem Benzylierungsmittel 7,2-Dibenzyl-3-oxo-2,3-dihydro-indazol (43 "4) liefert. 

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