Cyanohydrins inclusion complex

Very interestingly, all cyanohydrins (61h-m) which are substituted with one phenyl group and one less bulky alkyl group or hydrogen atom do not form inclusion complex with 4. However, the cyanohydrins which are substituted with two alkyl groups (62a-c) or with one alkyl group and one hydrogen atom (62d-f) formed complex with 4 and were resolved.27 3... 

Resolution of Ketones. Brucine has not been used very extensively for the resolution of neutral compounds. However, in some cases, ketones or ketone derivatives may form diastereomeric inclusion complexes with brucine, providing an opportunity for their resolution. For example, the cyanohydrin of a bicyclic ketone has been resolved by this procedure (eq 10). Following resolution of the cyanohydrin, the ketone was regenerated and determined to be of 94% ee. 

Alcohol and cyanohydrin guests easily form inclusion complexes with brucine host... 

ABSTRACT. Novel optical resolutions of guest compounds by inclusion complex formation with optically active host compound are reviewed Tertiary acetylenic alcohols, cyanohydrins, and secondary alcohols were resolved by complexation with alkaloids such as brucine or sparteine. Cycloalkanones, 2,3 -epoxycyclohexanones, and some other neutral compounds were resolved by complex formation with optically active diacetylenic diol. Mutual optical resolution of bis-g-naphthol and sulfoxides by complex formation was also reviewed. 

ImHNL is a nonglycosylated homodimer (84 kDa) which catalyzes the reversible cleavage of aliphatic (R)-cyanohydrins [34]. This HNL does not require complex protein modification after protein biosynthesis. Thus, expression in prokaryotic Escherichia coli) and eukaryotic hosts Pichia pastoris) is possible [35-37]. However, initial trials to express IwHNL in E. coli were hampered by formation of inclusion bodies [36]. 

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