Ratsami Lekphrom

Bioactive styryllactones and alkaloid from flowers of Goniothalamus laoticus

ETHNOPHARMACOLOGICAL RELEVANCE Goniothalamus laoticus (Annonaceae) is being used traditionally as a tonic and a febrifuge by the local people in the northeastern part of Thailand. AIM OF STUDY To investigate the Thai medicinal plant, Goniothalamus laoticus, for antiplasmodial, antimycobacterial and cytotoxicity activities. MATERIALS AND METHODS The flowers extracts of Goniothalamus laoticus were isolated by chromatographic techniques. Structures of isolated compounds were identified by spectroscopic methods. The antiplasmodial, antimycobacterial and cytotoxicity evaluation of styryllactone derivatives and alkaloid were also performed. RESULTS Ten compounds, cinnamic acid (1); dihydrochrysine (2); beta-sitosterol (3); six styryllactones, (+)-3-acetylaltholactone (4), goniotriol (5), (+)-altholactone (6), (+)-goniofufurone (7), 9-deoxygoniopypyrone (8), howiinin A (9); and an aporphine alkaloid; (-)-nordicentrine (10) were isolated from flowers of Goniothalamus laoticus. Among these, compounds 1, 3-5, 8-10 are first isolated from the Goniothalamus laoticus. Besides, compound 10 is the first report from the Goniothalamus genus. The isolated compounds were evaluated in antiplasmodial, antimycobacterial and anticancer cell lines tests. Compounds 4-6 and 10 exhibited antiplasmodial activity against Plasmodium falciparum (IC(50) 2.6, 7.9, 2.6 and 0.3 microg/mL, respectively), while 5, 6, 9 and 10 showed antimycobacterial activity against Mycobacterium tuberculosis (MIC 100, 6.25, 6.25 and 12.5 microg/mL, respectively). In addition, compounds 4-10 showed cytotoxicity against cancer cells, KB, BC1, NCI-H187, and MCF-7 with IC(50) ranging from 0.4 to 22.7 microg/mL. CONCLUSION This finding showed that the styryllactone derivatives and alkaloid isolated from the flowers of Goniothalamus laoticus exhibited antiplasmodial activity against Plasmodium falciparum, antimycobacterail against Mycobacterium tuberculosis and cytotoxicity against four cancer cell lines.

Bioactive Diterpenes from the Aerial Parts of Anisochilus harmandii

Two new diterpenes, 4- EPI-triptobenzene L ( 1) and 12- O-deacetyl-6- O-acetyl-19- acetyloxycoleon Q ( 2), as well as eight known diterpenes ( 3- 10) were isolated from the aerial parts of Anisochilus hamandii. Structures of the isolated compounds were identified from spectroscopic evidence. Compounds 1, 2, 5, and 10 exhibited antiplasmodial activity against Plasmodium falciparum (IC (50) 4.70, 2.90, 3.03, and 7.20 microg/mL, respectively), while 3, 5, and 7 showed antimycobacterial activity against Mycobacterium tuberculosis (MIC 50 microg/mL). In addition, only 10 showed strong cytotoxicity against NCI-H187 cells (IC (50) 4.43 microg/mL).

C-7 oxygenated coumarins from the fruits of Micromelum minutum

A new 7-oxygenated coumarin, 7-demethylmurralonginol isovalerate (1), and a new natural product, murralonginol (2), together with seven known 7-oxygenated coumarins, murralonginol isovalerate (3), murralongin (4), micromelin (5), scopoletin (6), microminutin (7), murrangatin (8), and minumicrolin (9), were isolated from the fruits of Micromelum minutum. The structures of these compounds were established on the basis of their 1D and 2D NMR spectroscopic data. Among these isolates, compounds 2 and 4–9 exhibited cytotoxicity against cholangiocarcinoma cell line, KKU-100.

Two new flavanonols from the bark of Akschindlium godefroyanum

The first phytochemical investigation of the bark of Akschindlium godefroyanum (Kuntze) H. Ohashi (Fabaceae), a Thai herbal medicine, resulted in the isolation of two new flavanonols, 7,3′,5′-trihydroxy-5-methoxyflavanonol (1) and 7,4′-dihydroxy-5,3′-dimethoxyflavanonol (2), and eight known compounds comprising one flavonol, geraldol (3); three flavanonols, (+)-taxifolin (4), (+)-fustin (5) and aromadendrin 5-methyl ether (6); one catechin, (–)-epigallocatechin (7); one triterpenoid, lupeol (8); one steroid, stigmasterol (9) and one steroid glycoside, stigmasterol-3-O-β-d-glucoside (10). Their structures were identified by spectroscopic methods.

Two new bioactive iridoids from Rothmannia wittii

The first reported study of the isolation and identification of compounds from the bark and fruit of Rothmannia wittii yielded two new iridoids, 6β-hydroxy-10-O-acetylgenipin (1) and 10-O-acetylmacrophyllide (2) together with six known iridoids; 6β-hydroxygenipin (3), genipin (4), garjasmine (5), cerbinal (6), and mixture of β-gardiol (7) and α-gardiol (8); benzoic acid (9); vanillic acid (10); and stigmasterol (11). Their structures were elucidated by spectroscopic methods. Iridoid 1 showed antimycobacterial activity against Mycobacterium tuberculosis with a MIC value of 12.50μg/mL. Iridoid 2 showed cytotoxicity against the NCI-H187 cancer cell line with an IC50 value of 6.82μg/mL. In addition, 2 and 5 exhibited weak cytotoxic activity against KB and MCF-7 cell lines, while 4 was active against the NCI-H187 cancer cell line.

Chemical constituents and biological activities from branches of Colubrina asiatica

Abstract Sixteen compounds were isolated from a Thai medicinal plant, Colubrina asiatica. The isolated compounds were elucidated on the basis of spectroscopic methods (IR, 1D and 2D NMR) as six triterpene acids (1–6), five steroids (7–11), one benzoic acid derivative (12), two peptides (13 and 14), one sesquiterpenoid (15) and one jujubogenin (16). Compounds 3 and 10 showed antimalarial activity against Plasmodium falciparum. Compound 5 showed antimycobacterial activity. Moreover, compounds 3, 5, 6, 10 and 14 exhibited weak cytotoxicity against cancer cell lines. Compounds 1–15 have been isolated for the first time from this plant.

Antimalarial polyoxygenated cyclohexene derivatives from the roots of Uvaria cherrevensis

Three new polyoxygenated cyclohexene derivatives named cherrevenisyls A and B (1 and 2), and ellipeiopsol E (3), along with fifteen known compounds, were isolated from the roots of Uvaria cherrevensis. Their structures were determined by spectroscopic methods including 2D NMR techniques and mass spectrometry. The absolute configurations of 1 and 2 were assigned. Compounds 1, 2 and 5 showed antimalarial activity against Plasmodium falciparum with IC50 ranging from 3.34-7.34μg/mL. Compounds 5-18 exhibited cytotoxicity against three cancer cell lines (KB, MCF-7 and NCI-H187) with IC50 values in ranging from 1.26-49.03μg/mL.

A new coumarin from the roots of Micromelum minutum

Abstract A new coumarin, minutuminolate (1), together with eleven known coumarins (2–12), was isolated from the roots of Micromelum minutum. The structures of these compounds were established on the basis of their 1D and 2D NMR spectroscopic data. Compounds 2, 5, 10, 11 and 12 showed cytotoxicity against KB cell line. In addition, compounds 2, 3, 4, 7, 11 and 12 also showed weak cytotoxicity against NCI-H187 cell line.

A novel cyclohexenone from Trachyspermum roxburghianum

Abstract A novel cyclohexenone, roxydienone (1), together with 13 known compounds (2–14), were isolated from the seeds of Trachyspermum roxburghianum. The structures of these compounds were established on the basis of their 1D and 2D NMR spectroscopic data. Compounds 1, 2, 7–9 and 14 showed cytotoxicity against NCI-H187 cell line while compounds 1 and 9 showed cytotoxicity against KB cell line. In addition, only compound 13 showed cytotoxicity against MCF-7 cell line.