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Aim: To study the chemical constituents of Lycianthes biflora., Methods: Column chromatography was used to separate the chemical constituents. IR, MS, 1HNMR, 13CNMR and 2D-NMR technique were used to determine the structures of the isolated constituents., Results: Five compounds were isolated from this plant. Their structures were identified to be bifloride A (1), N-trans-cinnamoyltyramine (2), liquiritigenin (3), N-trans-p-coumaroyloctopamine (4), 1-O-beta-D-glucopyranosyl-2-N-2'-hydroxypalmitoyl-sphinga-4- trans-8-trans-dienine (5)., Conclusion: Compounds 1 and 2 are new compounds, the others were isolated from this plant for the first time. Compound 2 showed inhibitory effects on P-388.

Two new prenylated flavones, named artoindonesianin A (1) and artoindonesianin B (2), were isolated from the root of Artocarpus champeden, together with a known prenylated flavone, artonin A. The structures of artoindonesianins A and B were determined on the basis of spectral evidence (MS, 1H and 13C NMR) and by comparison with known related compounds. Compounds 1 and 2 exhibited cytotoxic activity against murine leukemia (P-388) cells.

Saponins in bulbs of a mutant of elephant garlic were investigated, and three new steroidal saponins named yayoisaponins A-C were obtained together with the known dioscin and aginoside. Their structures, including the relative stereochemistry, were elucidated by spectral data interpretation, while the absolute stereochemistry of the sugar moieties was assigned on the basis of a chiral gas chromatographic analysis of the acid hydrolysates. Yayoisaponins A-C and aginoside exhibited not only in vitro cytotoxicity against P388 cells at 2.1 micrograms/ml, but also antifungal activity against Mortierella ramanniana at 10 micrograms/disk.

Two new cyclic octapeptides, dichotomin H, cyclo(-Ala-Pro-Thr-Phe-Tyr-P ro-Leu-Ile-), and dichotomin I, cyclo(-Val-Pro-Thr-Phe-Tyr-Pro-Leu-Ile-) have been isolated from the roots of Stellaria dichotoma L. var lanceolata Bge., and their structures were elucidated by extensive two-dimensional NMR methods and chemical degradation.

Three new antitumor sesquiterpenoids, achimillic acids A, B and C, were isolated as methyl esters from Achillea millefolium and their structures were determined spectroscopically. The compounds were found to be active against mouse P-388 leukemia cells in vivo.

Bioassay-directed fractionation of the MeCOEt extract of Porella cordeana yielded drimenin [1] and aristolone [4], which were moderately toxic towards DNA-repair-deficient mutants of Saccharomyces cerevisiae. Three inactive sesquiterpenes, 7-ketoisodrimenin [2], 7-ketoisodrimenin-5-ene [3], and norpinguisanolide, were also obtained. Compounds 2 and 3 are new.

Four new bicyclic hexapeptides, named as RA-XI, -XII, XIII and -XIV were isolated from Rubia cordifolia and showed potent antitumor activities against P-388. The structures were elucidated from spectroscopic and chemical evidences. RA-XII, XIII and -XIV were proved to be unique bicyclic hexapeptidic glucosides.

Two new prenylated flavonoids, flemiphilippinin C (I) and flemiphilippinin D (II) have been isolated from the root of Flemingia philippinensis (Merr. et Rolfe) Li along with four known compounds. The structure of I and II were elucidated as 7-(.4'-hydroxy-3'-methoxyphenyl)-5-hydroxy-2, 2-dimethyl-10-prenyl-2H,6H-benzo-[1,2-b:5,4-b']dipyran-6-one and 5,7,2',4'-tetrahydroxy-6,8-diprenylisoflavanone, respectively, on the basis of chemical and spectroscopic data. The four known compounds were identified as 5,7,3',4'-tetrahydroxy-6,8-diprenylsilflavone (III), flemichin D (IV), beta-sitosterol (VI) and lupeol (VII), and a mixture of n C22-C30 aliphatic acid (V). Compounds III and IV showed significant cytotoxic activities against P388 cell cultures.

Alkylehter and ester derivatives of the antitumor cyclic hexapeptide RA-V obtained from the roots of Rubia cordifolia (Rubiaceae) were synthesized and bioassayed for activity against cultured tumor cells. RA-V and its n-hexylether showed significant effects against human nasopharynx carcinoma (KB), P388 lymphocytic leukemia and MM2 mammary carcinoma cells. The activity values (log 1/IC50) of ether derivatives of RA-V gave an upward parabolic or bilinear relationship when plotted against log P (P: partition coefficient determined with the 1-octanol/water system) as the carbon number of the side chain at the phenol moiety of RA-V was increased, the optimum log P values being in the range from 3.5 to 4.9. The ester derivatives showed a similar relationship, the optimum log P values being 6.3-6.7, which is higher than that of the ether derivatives. The lethal effect of RA-V on KB cells was clearly different from that of mitomycin C, and RA-V was concluded to be a "time-dependent drug" like vinblastine.

The CHCl3-soluble fraction of a crude extract of Kmeria duperreana exhibited cytotoxic activity when tested in both KB and P388 tumor-cell cultures. Bioassay-directed fractionation led to the isolation of a cytotoxic alkaloid, liriodenine (1). Other constituents obtained from the extract included scopoletin (2), (-)-3,4,5-trimethoxyphenyl beta-D-glucopyranoside (3), (+)-syringaresinol beta-D-glucopyranoside (4), and a new phenylpropanol, kmeriol (5), whose chemical structure was established through spectroscopic analysis.

Employing the roots of Iris missouriensis, two known triterpenes, iso-iridogermanal and zeorin, were isolated and identified. As presently reported, they were found to demonstrate cytotoxic activity toward cultured P-388 cells (ED50 = 0.1 and 1.1 microgram/mL, respectively). Additionally, a new triterpene that demonstrated an ED50 of 8.5 micrograms/mL was isolated. On the basis of spectral analysis and chemical correlation with zeorin, the structure was shown to be 6 6 alpha-hydroxy-A'-neogermmacer-22(29)-en-30-oic acid (missourin).

As part of a continuing effort to provide novel agents of potential value in cancer chemotherapy, 2-hydroxy-3-octadecyl-5-methoxy-1,4-benzoquinone (irisoquin) was identified as a component of Iris missouriensis. This novel species demonstrated cytotoxic activity with cultured KB and P-388 cells (ED50 = 1.8 and 0.03 microgram/mL, respectively). The structure was assigned on the basis of spectral analyses and The structure was assigned on the basis of spectral analyses and confirmed by chemical synthesis. The latter provides a facile method for the production of irisoquin and structural derivatives that may be of value for the examination of structure-activity relationships. A closely related compound, 3-octadecyl-5-methoxy-1,4-benzoquinone (deoxyirisoquin), was also isolated from Iris missouriensis, prepared synthetically, and found to be devoid of cytotoxic activity.

Investigation of the leaves of Montanoa tomentosa Cerv. ssp. microcephala (Sch.-Bip.) Funk (Compositae) resulted in the isolation of three novel guaianolide sesquiterpenes, montacephalin (1), tomencephalin (2), and 5-hydroxytomencephalin (3), which were shown to be cytotoxic (P-388). The structures of these sesquiterpenes were elucidated through analysis of their spectroscopic characteristics, and complete proton and carbon-13 assignments were made for the new compounds. Also isolated were the known terpenes, beta-amyrin, beta-amyrin acetate, stigmasterol, stigmasterol-3 beta-D-glucoside, (-)-kaur-16-en-19-oic acid, and monoginoic acid.

An antitumor principle from Suillus granulatus has been identified as suillin. In vitro and in vivo activities against P-388 leukemia have been determined.

4-Hydroxy-25-desoxyneorollinicin, a new linear bistetrahydrofuranoid acetogenin, has been isolated from Rollinia papilionella. The structure was elucidated from high resolution mass spectral and nmr data. The relative stereochemistry of six of the eight stereogenic centers was established by analysis of the 1H-nmr spectra of the triacetate of 2. In addition, the relative stereochemistry of seven of the eight stereogenic centers of rollinicin, a previously reported bistetrahydrofuranoid acetogenin, was established by analysis of the 1H nmr spectra of the triacetate of 1 and the mass spectra of the tristrimethylsilyl ether of 1.

Three cytotoxic, quassinoid glycosides, the new bruceantinoside C [1] and the known yadanziosides G [2] and N [3] were isolated from the stem of Brucea antidysenterica. The structures of 1-3 were determined from their spectral data.