Prenylated flavonoids and related compounds of the Indonesian Artocarpus (Moraceae)

Abstract

Several species of the genus Artocarpus (Moraceae) have been investigated in our laboratories during the last decade. Over 60 phenolic constituents have been discovered and characterized, including 27 new compounds from 13 Indonesian taxa of Artocarpus, namely A. champeden, A. lanceifolius, A. teysmanii, A. scortechinii, A. rotunda, A. maingayi, A. kemando, A. bracteata, A. altilis, A. fretessi, A. gomezianus, A. reticulatus and A. glaucus. The principal and the most pronounced features of these phenolic constituents are the assembly of an isoprenyl substituent at C-3 of a flavone skeleton by closure of an ether bridge or a carbon-carbon linkage with the B ring of the skeleton, which may further rearrange into xanthone to produce various classes of natural products. The structures of the new and unusual natural products are presented. Many of the metabolites also exhibit cytotoxic effect against murine leukemia P388 cells.

Flavonoids from the Fresh Leaves of Kalanchoe tomentosa (Crassulaceae)

“…The cytotoxic effects of the three isolated compounds 1-3 against the P-388 murine leukimia cells were conducted according to the method described in previous paper [19,20] and were used an artonin E (IC 50 0.3 μg/mL) as a positive control [21]. Compounds 1-3 showed cytotoxicity against P-388 murine leukimia cells with IC 50 values of 51.8, 100 and 3.32 μg/mL, respectively, suggested that the presence of rhamnoside sugar unit in flavonoid structure can increase cytotoxic activity whereas the presence of glucoside unit can decrease cytotoxic activity.…”

New Cytotoxic Pregnane-type Steroid from the Stem Bark of Aglaia elliptica (Meliaceae)

“…The cytotoxicity values of the four isolated compounds 1-4 against the P388 murine leukemia cells were conducted based on experiment in previous paper [8,24,25] and artonin E (IC50 0.75 µg/mL) used as a positive control [26].…”

KECENDERUNGAN POLA OKSIDASI FLAVONOID PADA KULIT BATANG DAN KAYU BATANG Artocarpus scortechinii KING. (Moraceae)

“…Selain itu artoindonesianin E (3) ditemukan pula dari kulit batang A. champeden [10]. Senyawa flavanon terprenilasi pada posisi C-6 atau C-8 telah diisolasi dari akar dan buah A. heterophyllus yaitu heteroflavanone C (4) [11].…”

“…Secara biogenesis, senyawa oksepinoflavon dapat berasal dari senyawa 2',4'-dioksigenasi atau 2',4',5'-trioksigenasi 3-prenilflavon (sebagai prekursor), melalui reaksi siklisasi oksidatif yang melibatkan pembentukan ikatan -C-O-C-antara gugus OH pada C-2' dengan C-10 dari gugus isopren pada C-3. Senyawa caplasin (21) merupakan senyawa pertama dari golongan oksepinoflavon yang berhasil diisolasi dari Artocarpus, yaitu dari A. maingayii [10]. Selain itu, artoindonesianin B (22) merupakan senyawa golongan oksepinoflavon yang berhasil diisolasi dan dikarakterisasi dari A. champeden [14].…”

“…Data metabolit sekunder yang berhasil diisolasi dari kulit batang A. scortechinii King sejauh ini ada delapan senyawa yaitu norartokarpetin (8), artonin E (17), artobiloksanton (23), sikloartobiloksanton (24), 5'-kudraflavon A (25), artoindonesianin C (26), artonol A (27), dan artonol B (28) [10]. Dari data metabolit sekunder tersebut memperlihatkan kecenderungan pola oksigenasi pada cincin B dari kerangka flavon pada posisi 2', 4' dan 5'.…”