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Grewia Bicolor: 6-HO-Harman, 6-MeO-Harman, Harman

Migrated topic.
I always found it interesting that betacarbolines also show up in the Tiliaceae. Do you have access to this plant? Just how widespread is 'widespread'? IIRC, Shulgin and/or Ott listed Grewia villosa as containing 6-MeO-harman derivatives as well, although it would be wise to check for conspecificities and synonyms with all this stuff. And, incidentally, cowitch, Mucuna pruriens has 6-MeO-something listed among its constituents as well.

Furthermore, it seems we don't really know anything about the pharmacology of these 6-MeO compounds. In that respect, the guinea pig uterus contraction result might be seen by some as a promising indication of interesting central activity.
7-Substituted analogues of harman are well known and widely distributed alkaloids; the 6-substituted compounds which were found in this investigation are rare and only found in some Virola species (Allan and Holmstedt, 1980) and in Grewia mollis (Rosler et al., 1978; Allan and Holmstedt, 1980). Because no compounds were isolated from the roots which could be responsible for their use in delayed afterbirth, ethanolic extracts were tested on the guinea pig uterus, showing strong contractions which were not blocked by atropine. Contractions caused by the extract and 5-HT (serotonin) were both blocked with the semisynthetic ergot alkaloid methysergide. On the contracting uterus methanol extracts of the roots gave an increase of the frequency and force of the contractions.

Paris (1956) and Paris and Theallet (1961) reported that extracts from the bark of different Grewia species, amongst them Grewia bicolor hss. showed an oxytocic activity. Although they isolated an active constituent these authors could not establish its structure. Research is now being carried out to isolate and identify the oxytocic principle of Grewia roots.
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Not widespread in western world. Widespread in Africa from southern to western and central Africa. Also prevalent in middle east and India.

Quite a big genus and I think in several cultures an alcoholic drink is made with the sweet berries of some species.

G. Bicolor is present in my country though not in my area. If I get the chance, I will collect some samples. Hope to test some other Grewia species as well eventually.

Edit: Grewia mollis has also been found to contain 6-HO-Harman. I can't find the paper, but it is cited in another paper as:

Rosler H.; Framm, H.; Blomster, R.N. The isolation of 6-hydroxyharman from Grevia mollis.
Lloydia 1978, 41, 383–384.

Also, DFZ, Are you sure M. Pruriens would be considered part of Tiliaceae? I cannot find information supporting this.
 
Ah, no - I wasn't intending to suggest that M. pruriens resides within the Tiliaceae. It's Fabaceae AFAIK, being a bean. It was merely an observation that I seem to recall it being listed among those plants which contain an oxy-something substituent at the 6-position of a betacarboline. Sorry for perhaps being a bit vague!

Old back-issues of Lloydia seem to be really difficult to get hold of! There are so many Lloydia articles that I'd love to read but have never been able to find - it seems like we could do with a collective effort within the Nexus to overcome this barrier to research. There must be somebody out there with a huge back-catalogue of them - but who? Did Lloydia contain so many hidden gems of ethnobotany that their owners decided to keep them out of the public sphere?
 
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