Pyranocoumarins from Tropical Species of the Genus Calophyllum:  A Chemotaxonomic Study of Extracts in the National Cancer Institute Collection

Abstract

(+)-Calanolide A, a novel dipyranocoumarin from the Malesian tree Calophyllum lanigerum var. austrocoriaceum, and a closely related compound, (-)-calanolide B, isolated from Calophyllum teysmannii var. inophylloide, are representatives of a distinct class of nonnucleoside HIV-1 specific reverse-transcriptase inhibitor under development as an AIDS chemotherapeutic. NCI repository specimens totalling 315 organic extracts from 31 taxa of Calophyllum were analyzed for related pyranocoumarins using a simple TLC system. A total of 127 extracts was initially classified as "positive"; eight out of the 31 taxa examined, representing perhaps 28 species already described (1/7-1/8 of all the species in this genus), contained prenylated coumarins, suggesting that these compounds, while sometimes abundantly present, are not widespread in the genus. Representative members of the TLC-positive extracts were partitioned between CH2C12 and 25% aqueous MeOH; the CH2C12-soluble materials were then analyzed by TLC and 1H NMR to confirm the presence of pyranocoumarins. The anti-HIV activity of the partitioned extracts are also presented. This study suggested that there are several distinctive coumarin chemotaxonomic markers distinguishing species of this genus.

Apoptosis inducing activity of 4-substituted coumarins from Calophyllum brasiliense in human leukaemia HL-60 cells

“…Since then, the chemical constituents of Calophyllum species have been actively studied (Patil et al 1993;Taylor et al 1994;Currens et al 1996;Zembower et al 1997;McKee et al 1998;Ishikawa 2000;Sekino et al 2004). Systematic studies of the chemical constituents of Calophyllum plants have been conducted by our group, and we showed that C. brasiliense Camb.…”

5,9,11-Trihydroxy-2,2-dimethyl-3-(2-methylbut-3-en-2-yl)pyrano[2,3-a]xanthen-12(2H)-one from the Stem Bark of Calophyllum tetrapterum Miq.

“…This genus is well known to be a rich source of bioactive xanthones [1][2][3][4], coumarins [5][6][7], chromanone acids [8][9][10][11], and flavonoids [12]. Some these were reported to exhibit of biological activities including anti-HIV, anticancer, antimalarial and antimicrobial [13,14].…”

5,9,11-Trihydroxy-10-(2″-hydroxy-3″-methylbut-3″-en-1-yl)-2,2-dimethyl-3-(2′-methylbut-3′-en-2′-yl)-2H,12H-pyrano[2,3-a]xanthen-12-one from Calophyllum pseudomole

“…This genus has been shown to possess a number of secondary metabolites such as xanthones [1][2][3], coumarins [4,5], and chromanone acids [6,7]. Many of these compounds have shown a wide range of biological and pharmacological properties such as anti-HIV [8,9], anticancer [10,11], and antimalarial properties [12].…”

“…This genus has been shown to possess a number of secondary metabolites such as xanthones [1][2][3], coumarins [4,5], and chromanone acids [6,7]. Many of these compounds have shown a wide range of biological and pharmacological properties such as anti-HIV [8,9], anticancer [10,11], and antimalarial properties [12]. In continuation of our phytochemical investigation on bioactive xanthone, we wish to report the isolation and structural elucidation of a new pyranoxanthone, 5,9,11-trihydroxy-10-(2″-hydroxy- In continuation of our phytochemical investigation on bioactive xanthone, we wish to report the isolation and structural elucidation of a new pyranoxanthone, 5,9,11-trihydroxy-10-(2 -hydroxy-3 -methylbut-3 -en-1-yl)-2,2-dimethyl-3-(2 -methylbut-3 -en-2 -yl)-2H,12H-pyrano[2,3-a]xanthen-12-one ( Figure 1) from the stem bark of Calophyllum pseudomole.…”