Demethyl-coclaurine

Nelumbium nelumbo Druce. Lian Zi Xin (Lotus) (plumule) Liensinine, isoliensinine, neferine, lotusine, methyl-corypalline, demethyl-coclaurine.33 Tranquilizing and antihypertensive. 

The biosynthesis of cocsulin (63) and cocsulinin (64) in Cocculus laurifolius has been found to parallel that of tiliacorine and tiliacorinine (above). Thus bpth are formed from two units of iV-methylcoclaurine (60), without iV-demethylation [coclaurine (59) and norcoclaurine (58) were also incorporated an incorporation... 

Stephania glabra (Roxb.) was shown to produce cycleanine (112) and N-desmethylcycleanine (129) via dimerization of both (R)-lV-methylcoclaurine (69) and (R)-coclaurine (although the racemic form of the latter was used in these experiments). The plant was proven to utilize L-tyrosine to biosynthesize the intermediate Af-methylcoclaurine. The exact sequence of dimerization-Af-meth-ylation/N-demethylation has not yet been determined (346). 

Coclaurine is an important alkaloid because its demethyl analog, norco-claurine, can be regarded as the prototype building block of dimeric benzylisoquinoline alkaloid that are often referred to as biscoclaurine-type alkaloids. 

Chronotropic effect, positive Coclaurine, (DL)-N-demethyl Isoquinoline alkaloid 400... 

The conversion of isoboldine (33) into boldine (34) involves demethylation and remethylation rather than methyl transfer since boldine (34) derived from [6-Ol CH3, l- H]reticuline [as (25)J showed a 64% loss of label. Parallel results were observed for the biosynthesis of the naturally occurring dienone, crotonosine (45), from (R)-coclaurine [as (24)] (Haynes et al. 1965). 

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