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A novel type of alpha,beta-butenolide alkaloid, uncinine (1), two novel oxoaporphines, artabonatine C (2) and artabonatine D (3), a new oxazoloaporphine, artabonatine E (4), and a new 7,7'-bisdehydroaporphine, artabonatine F (5), along with 25 known alkaloids, were isolated from Artabotrys uncinatus. The structures of 1-5 were determined using NMR and mass spectral data. Atherospermidine and squamolone exhibited cytotoxicity against hepatocarcinoma cancer cell lines (Hep G(2) and 2,2,15), and the activity of some of the alkaloids in an antithrombin assay is also discussed.

A novel alkaloid, hydrachine A (3), has been isolated, along with 15 known compounds, from the roots of Hydrangea chinensis. The structure and stereochemistry of the new alkaloid 3 was determined using extensive 2D NMR data.

Seven new annonaceous acetogenins, muricins A-G (1-7), as well as five known compounds, a mixture of muricatetrocin A (8) and muricatetrocin B (9), longifolicin (10), corossolin (11), and corossolone (12), were isolated from the seeds of Annona muricata. The structures of all isolates were elucidated and characterized by spectral and chemical methods. These acetogenins showed significantly selective in vitro cytotoxicities toward the human hepatoma cell lines Hep G(2) and 2,2,15.

A new guaipyridine sesquiterpene alkaloid, cananodine (1), and two new eudesmane sesquiterpenes, cryptomeridiol 11-alpha-L-rhamnoside (2) and gamma-eudesmol 11-alpha-L-rhamnoside (3), along with gamma-eudesmol (4), were isolated from the fruits of Cananga odorata. The structures of compounds 1-3 were established on the basis of NMR and MS methods. In addition, compounds 1-4 and four previously reported alkaloids, cleistopholine (5), N-trans-feruloyltyramine (6), (+)-ushinsunine-beta-N-oxide (7), and lyscamine (8), were evaluated for cytotoxicity against two human hepatocarcinoma cell lines.

A new halimane diterpene, 3beta,5beta, 16alpha-trihydroxyhalima-13(14)-en-15,16-olide (1), and a new oxoprotoberberine alkaloid, (-)-8-oxopolyalthiaine (2), along with 20 known compounds, were isolated from a methanolic extract of Polyalthia longifolia var. pendula. The structures of compounds 1 and 2 were established by spectroscopic analysis. Several of these compounds were evaluated for cytotoxicity toward a small panel of human cell lines.

Investigation of extracts of Fissistigma balansae and Fissistigma oldhamii resulted in the isolation of 11 aristolactams-stigmalactam (1), piperolactam A (2), piperolactam C (3), aristolactam AII (4), aristolactam AIIIa (5), aristolactam BII (6), aristolactam BIII (7), aristolactam FII (8), goniothalactam (9), enterocarpam I (10), and velutinam (11)-as well as two dioxoaporphines, noraristolodione (12) and norcepharadione B (13). The new compound 1 was identified by spectral data interpretation. Compounds 1-13 were subjected to antiplatelet aggregation testing.

Three new kaurane diterpenoids, annoglabasin C (16alpha-acetoxy-ent-kauran-19-oic acid-17-methyl ester) (1), annoglabasin D (16alpha-acetoxy-ent-kauran-19-al-17-methyl ester) (2), and annoglabasin E (16alpha-hydro-19-ol-ent-kauran-17-oic acid) (3), and a new norkaurane diterpenoid, annoglabasin F (16alpha-acetoxy-19-nor-ent-kauran-4alpha-ol-17-methyl ester) (4), along with 13 known kaurane derivatives were isolated from the stems of Annona glabra. 16alpha-Methoxy-ent-kauran-19-oic acid (5) and 16alpha-hydro-ent-kauran-17,19-dimethyl ester (6) were obtained for the first time as natural products. The structures of compounds 1-6 were characterized by spectral analysis.

Three new alkaloids, promucosine (1), romucosine F (2), and romucosine G (3), along with 28 known compounds, were isolated from the MeOH extract of stems of Annona purpurea. The structures of 1-3 were determined on the basis of spectral data and chemical evidence.

From the underground parts of Tupistra chinensis, a novel polyhydroxylated spirostanol sapogenin, tupichigenin A [(20S, 22R)-spirost-25(27)-ene-1beta,2beta,3beta,5beta- tetraol] (1), was isolated and determined structurally on the basis of spectroscopic methods. Also isolated was the known steroidal sapogenin (20S, 22R)-spirost-25(27)-ene-1beta,2beta,3beta,4beta, 5beta, 7alpha-hexaol-6-one (2).

Four new compounds, a mixture of 20,23-cis-2,4-trans-bullatalicinone (1) and 20,23-cis-2,4-cis-bullatalicinone (2), rollimusin (3), and rolliacocin (4), along with eight known acetogenins, were isolated from an ethyl acetate extract of the unripe fruits of Rollinia mucosa. The structures and stereochemistry of 1-4 were determined on the basis of spectral data and chemical evidence.

Bioactivity-directed fractionation led to the isolation of 19 compounds, including three oxoaporphines, oxopurpureine (5), oxonuciferine (6), and oxoglaucine (7); three aporphines, (+)-predicentrine (8), (-)-glaucine (9), and thalbaicalidine (10); one aporphine sensu stricto, N-formyl-purpureine (11); one proaporphine, glaziovine; one phenanthrene, thalicpureine (12); two 6a,7-dehydroaporphines, dehydrolirinidine (13) and 7-hydroxy-dehydroglaucine (14); four flavonoids, quercetin-3-O-rhamnoside, kaempferol-3-O-rhamnoside, isorhamnetin-3-O-rhamnoside, and tanarixetin-3-O-rhamnoside; one purine, adenine; one lactam amide, squamolone; and two steroids, beta-sitosterol and beta-sitosterol-beta-D-glucoside from the MeOH extract of the leaves of Formosan Annona purpurea. Among them, 11-14 were characterized as new compounds and alkaloids, 5-8, 10, and 12-14 exhibited significant antiplatelet aggregation activity.

Using a bioassay-directed fractionation method, three new compounds, including an aporphine alkaloid, cassyformine (4); an oxoaporphine alkaloid, filiformine (8), and a lignan, (+)-diasyringaresinol (10), along with 14 known compounds, were further isolated and characterized from the MeOH extract of the fresh herbs of Cassytha filiformis. Among the isolates of this plant, cathafiline (1), cathaformine (2), actinodaphnine (3), N-methylactinodaphnine (5), predicentrine (6), and ocoteine (7) exhibited significant antiplatelet aggregation activity.

Phytochemical analysis of the fruits of Annona glabra yielded two new kaurane diterpenoids, annoglabasin A (methyl-16 beta-acetoxy-19-al-ent-kauran-17-oate)(1) and annoglabasin B (16 alpha-hydro-19-acetoxy-ent-kauran-17-oic acid)(2), along with 11 known kaurane derivatives (3-13). The structures of the new compounds were established by spectral and chemical evidence. Among these, methyl-16 alpha-hydro-19-al-ent-kauran-17-oate (11) exhibited mild activity against HIV replication in H9 lymphocyte cells, and 16 alpha-17-dihydroxy-ent-kauran-19-oic acid (4) showed significant inhibition of HIV-reverse transcriptase.

A new hexacyclic triterpenoid, mudanpinoic acid A (1), and a new gallic acid glycoside, mudanoside B (2), along with nine known compounds--benzoic acid, resacetophenone, paeoniflorigenone, beta-sitosterol, betulinic acid, oleanoic acid, quercetin, beta-sitosterol-beta-D-glucoside, and trans-caffeic acid stearyl ester-were isolated from the dried root cortex of Paeonia suffruticosa. The structures of the novel compounds were elucidated on the basis of spectral methods, and that of compound 1 was confirmed by X-ray crystallographic analysis.

Using antiplatelet aggregation as a guide to fractionation, seven aporphines, actinodaphnine (1), N-methylactinodaphnine (2), launobine (3), dicentrine (4), O-methylbulbocapnine (5), hernovine (7), and bulbocapnine (9), and two oxoaporphines, dicentrinone (6) and liriodenine (8), were isolated from the stems of Illigera luzonensis. Among them, compounds 2, 4, 5, 8, and 9 were isolated for the first time from this species. Moreover, compounds 1-5, and 8 showed significant antiplatelet aggregation and compounds 1 and 6 exhibited significant vasorelaxant activities, respectively.

Phytochemical analysis of the fruits of Annona squamosa yielded 12 known kaurane derivatives (1-11, 13) and two new kaurane diterpenoids, which have been named annosquamosin A (16 beta-hydroxy-17-acetoxy-ent-kauran-19-al) (12) and annosquamosin B (19-nor-ent-kaurane-4 alpha,16 beta,-17-triol) (14). The structures of the new compounds were established by spectral analyses and chemical evidence. Among these 14 compounds, 16 beta, 17-dihydroxy-ent-kauran-19-oic acid (2) showed significant activity against HIV replication in H9 lymphocyte cells with an EC50 value of 0.8 microgram/mL (therapeutic index > 5).

Members of a series of benzylisoquinoline and phenanthrene alkaloids were tested for their antiplatelet and vasorelaxing actions. Atherosperminine HClO4 (15) and atherosperminium I (16) showed strong inhibition of adenosine 5'-diphosphate-induced platelet aggregation. dl-N-Methylcoclaurine (1), dl-coclaurine (6), 15, 16, xylopine hydroxylamine (18), and atherosperminine N-oxide (19) showed strong inhibition of arachidonic acid-induced platelet aggregation. Compounds 1, 15, 16, dicentrine methine (17), 18, and 19 showed strong inhibition of collagen-induced platelet aggregation. d-(-)-Magnocurarine I (8), 15, and 16 showed strong inhibition of platelet-activating factor-induced platelet aggregation. Compounds 15, 17, and 19 showed vasorelaxing action in rat thoracic aorta.

Using cytotoxicity as a guide to fractionation, one novel acetogenin, annoreticuin-9-one [3], and four known cytotoxic acetogenins, squamone [4], solamin [5], annomonicin [6] and rolliniastatin 2 [7], were isolated from active extracts of the leaves of the Formosan plant Annona reticulata. Their structures were elucidated on the basis of uv, ir, 1H- and 13C-nmr, and ms data of the natural compounds and their derivatives.

Bioactivity-guided fractionation of a CHCl3 extract of the soft coral Lobophytum michaelae afforded a new cytotoxic cembranolide, lobomichaolide (1), and a known cytotoxic cembranolide, crassolide (2). The structure of 1 was determined by spectral and X-ray crystallographic analysis.

The styrylpyrone, goniodiol-7-monoacetate [1] [6R-(7R,8R-dihydro-7-acetoxy-8-hydroxystyryl)-5, 6-dihydro-2-pyrone], has been isolated from Goniothalamus amuyon, and its detailed molecular structure has been determined by X-ray crystallographic analysis. Goniodiol-7-monoacetate showed potent (ED50 values less than 0.1 microgram/ml) cytotoxicities against KB, P-388, RPMI, and TE671 tumor cells.

Bioactivity-guided fractionation of a CHCl3 extract of the leaves of Piper aborescens afforded a new cytotoxic pyridone alkaloid, N-(3-methoxy-4,5-methylenedioxydihydrocinnamoyl)-delta 3-pyridin-2-one [1], as well as three known cytotoxic pyridone alkaloids, N-(3-methoxy-4,5-methylenedioxycinnamoyl)-delta 3-pyridin-2-one [2], piplartine [3], and piplartine dimer A [4].

The stem and stem bark of Polyalthia longifolia afforded the cytotoxic aporphine alkaloid liriodenine [1], as well as two aporphine alkaloids, noroliveroline [2] and oliveroline-beta-N-oxide [3] and three azafluorene alkaloids, darienine [4], polyfothine [6], and isooncodine [7], which are not bioactive. Polyfothine [6] and isooncodine [7] are new natural compounds.