Acasiane A and B and Farnesirane A and B, Diterpene Derivatives From the Roots ofAcacia farnesiana

Abstract

Four new diterpenes, acasiane A ( 1), acasiane B ( 2), farnesirane A ( 3), and farnesirane B ( 4), along with three known diterpenes ( 5 - 7), two triterpenes ( 8 and 9), and eight flavonoids ( 10 - 17) were isolated from the roots of Acacia farnesiana. The structures and relative configurations of these compounds were determined by various spectroscopic and x-ray analyses. All isolated compounds were evaluated for their in vitro cytotoxic activities against six human cancer cell lines (Hep G2, Hep 3B, MDA-MB-231, MCF-7, A549, and Ca9 - 22) with the MTT method. Betulinic acid ( 8) displayed moderate cytotoxicity (1.70 - 5.74 microg/mL) towards five human cancer cell lines and the flavonoids had slight effects. In addition, 8, diosmetin ( 13), and 3',4',5-trihydroxy-7-methoxyflavone ( 15) slightly inhibited superoxide anion generation or elastase release by human neutrophils, indicating moderate anti-inflammatory activities.

Identification of Novel Anti-inflammatory Agents from Ayurvedic Medicine for Prevention of Chronic Diseases: “Reverse Pharmacology” and “Bedside to Bench” Approach

“…Among all the isolated compounds viz., acasiane A & B, farnesirane A and farnesirane B, three diterpenes, two triterpenes, eight flavonoids, and betulinic acid showed moderate anti-inflammatory activities against five human cancer cell lines [17]. …”

Luteolin is a rare substrate of human catechol-O-methyltransferase favoring a para-methylation

“…Since COMT catalyzes the transfer of one methyl group from S ‐adenosyl‐ l ‐methionine to one of hydroxyls in catecholic substrates (depicted in Table ), it means that only one of the hydroxyls can be methylated. It has been known that these methylated metabolites of catecholic flavonoids still possess their own biological activities, such as anti‐oxidant and anti‐cancer effects But the position of methyl might affect their pharmacologic effects, for example, the flavonoid with a methoxylated group at the meta‐position offers a stronger anti‐angiogenesis activity than that with a para‐methoxyl . Therefore, it is necessary to elucidate the regioselectivity of methylation for catecholic flavonoids.…”

In vitro biological activities of niloticane, a new bioactive cassane diterpene from the bark of Acacia nilotica subsp. kraussiana

“…Several cassane diterpenes have been isolated from plants belonging to the Fabaceae, especially from the genus Caesalpinia (Matsuno et al, 2009;Van Kiem et al, 2005;Yadav et al, 2009). The isolation of cassane diterpenoids from Acacia jacquemontii have been previously reported by Joshi et al (1979) and four new diterpene derivatives from the roots of Acacia farnesiana were also recently described by Lin et al (2009). Some cassane diterpenoids were found to be moderate cytotoxic against human cancer cell lines (Lin et al, 2009;Matsuno et al, 2009).…”

“…The isolation of cassane diterpenoids from Acacia jacquemontii have been previously reported by Joshi et al (1979) and four new diterpene derivatives from the roots of Acacia farnesiana were also recently described by Lin et al (2009). Some cassane diterpenoids were found to be moderate cytotoxic against human cancer cell lines (Lin et al, 2009;Matsuno et al, 2009). Cassanes, known as phytocassane, have also been identified as phytoalexins in rice (Oryza sativa L.) and it was proposed that these compounds help to protect the plant against pathogenic fungi (Koga et al, 1995).…”