Phloroglucinol derivative

Diacetylphloroglucinol and its homologues have been prepared and found to be inhibitors of the herpes vims (188). Syzygiol (50), a skin tumor promotion inhibitor, has been prepared from phloroglucinol (189). The first natural morphogen (cell-differentiation agent) (51) has also been identified as a phloroglucinol derivative (190). 

It is the methyl ether of a, phloroglucinol derivative, related to coumarin. Its constitution is as follows —... 

In situ quantitation The absorption photometric analysis in reflectance was carried out either at the absorption maximum of the pyrogallol derivative at = 350 nm (Fig. lA) or at the absorption maximum of the phloroglucinol derivative at = 420 nm (Fig. IB). 

An TY, Ming DS, Hu LH, Liu SJ, Chen ZL. Polyprenylated phloroglucinol derivatives from Hypericum erectum. Phytochemistry 2002 59 395-398. 

Zhao F, Watanabe Y, Nozawa H, Daikonnya A, Kondo K and Kitanaka S. 2005. Prenylflavonoids and phloroglucinol derivatives from hops (Humulus lupulus). J Nat Prod 68(l) 43-49. 

SCHUZ, R., HELLER, W., HAHLBROCK, K., Substrate specificity of chalcone synthase from Petroselinum hortense formation of phloroglucinol derivatives from aliphatic substrates, J. Biol. Chern., 1983,258, 6730-6734. 

Gey, C Kyrylenko, S Hennig, L., Nguyen, L.H., Biittner, A., Pham, H.D. et al. (2007) Phloroglucinol derivatives guttiferone G, aristoforin, and hyperforin inhibitors of human sirtuins SIRTl and SIRT2. Angewandte Chemie, 119, 5311-5314. 

Foo, L.Y. et al., Proanthocyanidins from Lotuspedunculatus, Phytochemistry, 45, 1689, 1997. Steynberg, P.J. et al.. Acid-catalyzed rearrangements of flavan-4-phloroglucinol derivatives to novel 6-hydroxyphenyl-6a,llb-dihydro-677-[l]benzofuro[2,3-c]chromenes and hydroxyphenyl-3,2 -spirobi[dihydro[l]benzofurans], J. Chem. Soc., Perkin Trans. 1, 2395, 1997. 

The pharmacological activity of SJW extracts has recently been reviewed (55-58). Recent reports have shown that the antidepressant activity of Hypericum extracts can be attributed to the phloroglucinol derivative hyperforin (59-62), to the naphthodianthrones hypericin and pseudohypericin (18,63-65), and to several flavonoids (66-69). The role and the mechanisms of action of these different compounds are still a matter of debate. But, taking these previous findings together, it is likely that several constituents are responsible for the clinically observed antidepressant efficacy of SJW. 

Single- and multiple-dose pharmacokinetic studies with extracts of SJW were performed in rats and humans, which focused on the determination of plasma levels of the naphthodianthrones hypericin and pseudohypericin and the phloroglucinol derivative hyperforin. Results from pharmacokinetic... 

The resorcinol and phloroglucinol derivatives (Table IV) all precipitated rather completely as expected except for 3,5- and 2,4-dihydroxy-benzoic acids. Their precipitation was enhanced if phloroglucinol was added this indicates that formaldehyde substitution occurred but the products were too soluble and too polar to precipitate until crosslinked with phloroglucinol. It had been shown previously that phenols which did not react with formaldehyde were not appreciably entrained in the precipitate formed with those which did (21) (see Table X). Hydro-quinone derivatives, except for one which is also a resorcinol derivative, did not precipitate with formaldehyde (Table V). 

Tropical rainforest tree and Malaysian tree A number of natural products have been reported to interact with reverse transcriptase, i.e., baicalin, avarol, avarone, psycho-trine, phloroglucinol derivatives and, in particular, calanolides (from the tropical rainforest tree, Calophyllum lanigerum) and inophyllums (from the Malaysian tree, Calophyllum inophyllum). 

AVAROL, AVARONE, PSYCHOTRINE, AND PHLOROGLUCINOL DERIVATIVES (i.e., MALLOTOJAPONIN)... 

Avarol and avarone derivatives (from the Red Sea sponge Dysidea cinerea), the alkaloids psy-chotrine and O-methylpsychotrine (from ipecac, the dried rhizome and root of Cephaelis ipecacuanha), and phloroglucinol derivatives such as mallotojaponin, from the pericarps of Mallotus japonicus, have all been reported to inhibit the reverse transcriptase activity of HIV-1, noncom-petitively with respect to the natural substrate (dNTP). In neither case was the anti-HIV-1 activity determined in cell culture, so it is not clear whether any of these compounds is really an effective... 

Based on published procedures for preparing both di- and tri-N-protected tert-butoxycarbonyl (Boc) cyclam derivatives [27], we developed the alternate procedure shown in Scheme 2 for obtaining the tri-branched species 11 [28] as well as related procedures for the new tri-branched derivative 12 (see Scheme 3) [28], the linearly linked derivative 13 [28] and the linked cyclic derivative 14 [29], In the case of the phloroglucinol derivative, tri-Boc protected cyclam was first acylated with chloroacetyl chloride the resulting chloromethylamide was then used to trialkylate phloroglucinol in DMF at 70 °C over caesium carbonate as outlined in Scheme 3. Subsequent... 

Fukuyama, Y., Kaneshi, A., Tani, N. and Kodama, M. (1993) Subellinone, apolyisoprenylated phloroglucinol derivative from Garcinia subelliptica. Phytochemistry 33(2), 483-485. 

Fukuyama, Y., Minami, H. and Kuwayama, A. (1998) Garsubellins, polyisoprenylated phloroglucinol derivatives from Garcinia subelliptica. Phytochemistry 49(3), 853-857. 

Chromenes (Phe a-pyran) include encecalin (a phototoxic antimicrobial from various Asteraceae) and the phloroglucinol derivative mallotochromene (cytotoxic and an HIV-1 reverse transcriptase inhibitor). Precocene 1 (7-methoxy-2,2-dimethylchromene) and pre-cocene 2 (6,7-dimethoxy-2,2-dimethylchromene) produced by Ageratum species (Asteraceae) inhibit the production of insect juvenile hormone (JH) as a result of suicidal conversion of these pro-toxins to cytotoxic derivatives by the JH-producing insect cells. 

Because of the structural nature of the ADE systems, the most straightforward and obvious method to accomplish a model synthesis is by the implementation of a von Pechmann coumarin synthesis118 l31) on a suitable functionalized phloroglucinol derivative. These methods have indeed seen rather general utilization in their application to this type of model system synthesis. 

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