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An expeditious isolation method for the cembrane diterpene alcohols incensol (la) and serratol (2) has been developed from respectively African and Indian frankincense. The two native alcohols and a series of semisynthetic derivatives of incensol were evaluated for transient receptor potential vanilloid 3 (TRPV3) activation and the inhibition of NF-kappa B, the putative molecular targets underlying the psychotropic and anti-inflammatory activities of incensol acetate (IA, 1b). Serratol (2) was the most potent TRPV3 activator, outperforming by 2 orders of magnitude the reference agonist thymol and by 1 order of magnitude incensol acetate (1b). Acylation, epimerization, and oxidation did not significantly improve the affinity of incensol for TRPV3, while NF-kappa B inhibition, marginal for both natural alcohols, could be improved by esterification of incensol (1a) with lipophilic acids. Interestingly, incensol (1a) but not IA (1b) was a potent inhibitor of STAT3, raising the possibility that hydrolysis to incensol (1a) might be involved in the in vivo biological activity of IA (1b). Serratol was not amenable to chemical modification, but some marine cembranoids related to the frankincense diterpenoids showed a certain degree of TRPV3-activating properties, qualifying the aliphatic macrocyclic cembrane skeleton as a selective chemotype to explore the pharmacology of TRPV3, a thermo-TRP otherwise resistant to modulation by small molecules.

The separation of some anthrone-C-glucosyl constituents of aloe was carried out by isocratic capillary electrochromatography using a 50 μm l.D. column packed with 3 μm ODS silica gel. In comparison to HPLC mode, CEC resolution of aloins was obtained in a very short time with a high selectivity factor. The influence of mobile phase parameters (pH and ionic strength of the buffer, acetonitrile amount in the eluent etc.) on the retention of aloins was examined in order to improve the separation conditions and to study the retention mechanism. Efficiency was found to increase with decreasing the EOF up to a reduced plate height of about 2 at a reduced linear velocity of 0.3 mm s−1. This effect was ascribed to the fact that, under the buffer conditions used (pH 8), aloins are partially anionically charged, with a consequent low mass transfer between the mobile and stationary phases. However, resolution remains almost the same in a wide pH range permitting baseline separations of aloins in short analysis times. Since aloins are known to undergo fast degradation reaction dependent on pH, a kinetic study was also carried out. The method was extended to the analysis of aloins in food and cosmetic products.