Adamantyl compounds

The di-t-butyl-substituted silanols 40 and 41 result from hydrolysis during column chromatography of the corresponding triflates and have also been structurally characterized (240). The adamantyl compound... 

Attachment of the adamantyl group to the ring nitrogen atoms of 3,6-disubstituted [l,2,4]triazolo[5, l-c][l,2,4]tri-azines 51 has been studied by Ulomskii et al. <2002ZOR294> (Scheme 7). These authors found that two products, the A-3-adamantyl 52 and the iV-4-adamantyl compounds 53, can be formed, and the regioselectivity was found to markedly depend on the substituents. Thus, the 2-unsubstituted compound yielded 52 as the only product, whereas 2-methyl and 2-methylsulfano derivatrives afforded 4-adamantyl products 53 in poor to medium yields. 

Lomas and Dubois (113b) also reported that by substitution of 1-adamantyl group(s) for one or two of the ferf-butyl group(s) of di-rm-butyl-o-tolylcarbinol (74), the barrier to rotation was-considerably raised, AG at 200°C being 33.9 and 39.1 kcal/mol, respectively, for the mono-1-adamantyl and di-1-adamantyl compounds in dodecane. Being rigid, the 1-adamantyl group causes more steric interference in the transition state for rotation than does the rm-butyl. 

Corrazana et al. [32] have measured the enthalpy of inclusion of rimantidine, an adamantyl compound, into several cyclodextrins. The values of A//for inclusion of rimantidine in (3 cyclodextrin, 6-amino (3 cyclodextrin, and 3-amino (3 cyclodextrin, respectively, are —28.60 + 0.16kJ moU —25.02 + 0.13kJ moU, and —17.29 + 0.18 kJ moU Calculate the values of A//for transfer of rimantidine from each cyclodextrin to each of the others. We can write the equations for the inclusion process as ... 

Why does the adamantyl compound shown below behave more like a ketone than an amide Hint Draw the corresponding resonance hybrid.)... 

An alkylation by reductive amination using aldehyde 253 in the presence of sodium triacetoxyborohydride in 1,2-dichloroethane afforded the adamantyl compound 253, which after further deprotection produced an A, A -disu Instituted guanidine derivative 254 interesting for potential biological activity (Scheme 105 <2000JME2362>). 

The invention [87] relates to the discovery that specific adamantyl or adamantyl group derivatives containing retinoid-related compounds induce apoptosis of cancer cells and therefore may be used for the treatment of cancer, including advanced cancer. It has been shown that such adamantyl compounds, e.g., 2-[3-(l-adamantyl)-4-methoxyphenyl]-5-benzimidazole carboxylic acid 135), can be used to treat or prevent cervical cancers. 

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