Effect of Terminal Alkyl Tail Length

The degree of unsaturation is not the only acyl chain requirement for reeogtrition at the CB, reeeptor. Sheskin and eo-workers (1997) found that in an n-3 series, highly unsaturated analogs had poor to no CBi affinity as revealed by the following series of n-3 ethanolamide derivatives 20 5,  

Sheskin and co-workers (1997) also found that the 18 3, A 3 (n-6) ethanolamide has low CB, affinity (K, = 4600 300 nM). This result suggests that a C18 aeyl ehain is too short to be recognized by CB, because this analog has both a long enough samrated tail (five carbons) and three ds homoallylic double bonds separated by methylene carbons. 

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