Unusual cyclolanostanes from leaves of Pandanus boninensis

A new lignan from Pandanus tectorius

A new lignan, named (8S, 8'S)-2,2',3,3'-tetramethoxy-4'-hydroxy-epoxylignan-4-O-β-D-glucoside (1), together with eight known compounds (2-9), was isolated from the leaves of P. tectorius. Their structures were elucidated on the basis of spectral characteristics and comparison with the data of literatures. Besides, the absolute configuration of 1 was established by using ECD calculations. The cytotoxicity of 1 in vitro against three selected tumor cell lines (A549, HeLa and MCF-7) was evaluated by MTT assay. The results showed that compound 1 exhibited moderate cytotoxicity against HeLa cell with IC₅₀ value of 19.30 ± 4.46 μM.

Constituents of the Leaves of Pandanus Utilis

Nineteen compounds, including seven triterpenoids (1–7), five steroids (8–12), four cyclohexenone derivatives (13–16), two benzenoid glycosides (17 and 18) and one lignan (19), were isolated and separated from the leaves of Pandanus utilis through bioactivity-guided fractionation. Among them, one new lanosterol-type triterpenoid was found and named as (24 R)-24-methyl-5α-4-demethyllanosta-9(11),25-dien-3β-ol (1). The structures of the isolates were determined by mass and spectroscopic analyses, and the compounds were subjected to anti-inflammatory, anti-oxidative and cytotoxic assays.

Alkaloids from Pandanus amaryllifolius: Isolation and Their Plausible Biosynthetic Formation

Pandanus amaryllifolius Roxb. (Pandanaceae) is used as a flavor and in folk medicine in Southeast Asia. The ethanolic crude extract of the aerial parts of P. amaryllifolius exhibited antioxidant, antibiofilm, and anti-inflammatory activities in previous studies. In the current investigation, the purification of the ethanolic extract yielded nine new compounds, including N-acetylnorpandamarilactonines A (1) and B (2); pandalizines A (3) and B (4); pandanmenyamine (5); pandamarilactones 2 (6) and 3 (7), and 5(E)-pandamarilactonine-32 (8); and pandalactonine (9). The isolated alkaloids, with either a γ-alkylidene-α,β-unsaturated-γ-lactone or γ-alkylidene-α,β-unsaturated-γ-lactam system, can be classified into five skeletons including norpandamarilactonine, indolizinone, pandanamine, pandamarilactone, and pandamarilactonine. A plausible biosynthetic route toward 1-5, 7, and 9 is proposed.

Pandalisines A and B, novel indolizidine alkaloids from the leaves of Pandanus utilis

Two novel alkaloids named pandalisines A (1) and B (2), constituting a new class of C8-substituted indolizidine moiety, were isolated from the leaves of Pandanus utilis. The structures of these new compounds were established by their mass and spectroscopic data. The absolute configuration was determined by the comparison of experimental CD and calculated ECD spectra. A plausible biosynthetic pathway for compounds 1 and 2 is advanced. The cytotoxic activities of the isolated alkaloids against A-549, Hep-G2, and MDA-MB-231 cancer cell lines were evaluated. The result showed that 1 and 2 are the first non-cytotoxic indolizidine alkaloids.

Isolation of pandamarilactonine-H from the roots of Pandanus amaryllifolius and synthesis of epi-pandamarilactonine-H

A new alkaloid (1a), named pandamarilactonine-H, which possesses a methyl-2-(pyrrolidin-2-yl)acetate function, was isolated from the roots of Pandanus amaryllifolius. Eleven known alkaloids were also isolated. Unambiguous assignment of the structure of 1a, including the absolute configuration, was accomplished by spectroscopic analysis and total synthesis of its enantiomer.

Terpenoids from the tuber of Cremastra appendiculata

Two new terpenoids including a cadinane sesquiterpene (1), and an ent-kaurane diterpene diglycoside (2), together with a known triterpene containing 32 carbons (3), have been isolated from the ethanolic extract of Cremastra appendiculata. Their structures were established by the spectroscopic methods including the IR, MS, 1D-, and 2D-NMR experiments as ( - )-cadin-4,10(15)-dien-11-oic acid (1), ( - )-ent-12beta-hydroxykaur-16-en-19-oic acid, 19-O-beta-D-xylopyranosyl-(1 --> 6)-O-beta-D-glucopyranoside (2), and (+)-24,24-dimethyl-25,32-cyclo-5alpha-lanosta-9(11)-en-3beta-ol (3). Compounds 1-3 were evaluated against several human cancer cell lines. Compound 3 showed in vitro-selective cytotoxicity against human breast cancer cell lines (MCF-7) with an IC50 of 3.18 microM, but 1 and 2 were inactive (IC50>10 microg/ml).

Triterpenoids

This review covers the isolation and structure determination of triterpenoids including squalene derivatives, protostanes, lanostanes, holostanes, cycloartanes, dammaranes, euphanes, tirucallanes, tetranortriterpenoids, quassinoids, lupanes, oleananes, friedelanes, ursanes, hopanes, isomalabaricanes and saponins. The literature from January 2005 to December 2006 is reviewed and 478 references are cited.

Three new furoquinoline alkaloids from the leaves of Boninia glabra

Three novel furoquinoline alkaloid oxogeranyl ethers (1-3) and one known furoquinoline alkaloid (4) were isolated from the leaves of Boninia glabra, an endemic plant of the Bonin Islands. Their structures were elucidated on the basis of spectroscopic analysis.