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Three polyketide compounds, surinone A, surinone B, surinone C and one acylresorcinol, suranone, along with thirty known compounds, were isolated from the whole plant of Peperomia sui. Their structures were elucidated from spectral analysis. Several compounds showed cytotoxic activity against HONE-1 and NUGC-3 cell lines in vitro.

A pyrrole alkaloid, pyrrolezanthine [5-hydroxymethyl-1-[2-(4-hydroxyphenyl)-ethyl]-1H-pyrrole-2-carbaldehyde]; a lignan, (-)-simulanol [4- [3-hydroxymethyl-5-((E)-3-hydroxypropenyl)-7-methoxy-2,3-dihydrobenzofuran-2-yl]-2,6-dimethoxy-phenol] and a monocyclic gamma-pyrone, zanthopyranone [3,5-dimethoxy-2-methyl-pyran-4-one], together with 28 known compounds were isolated from the stem wood of Formosan Zanthoxylum simulans. Their structures were determined through spectral analyses. Among the isolates, 11 compounds showed anti-platelet aggregation activity in vitro.

Bioassay-guided fractionation of the chloroform-soluble fraction from the stem wood of Formosan Lindera communis led to the isolation of two new cytotoxic butanolides, lincomolide C (1), lincomolide D (2), as well as two new secobutanolides, secolincomolide A (3), secolincomolide B (4), together with four known compounds, including one butanolide, isoobtusilactone A (5), and one secobutanolide, secoisolancifolide (6), one sesquiterpene, epi-cubenol (7), one steroid: beta-sitosterol (8). Compound 4 existed in enol [(2E)-2-[(1R)-1-hydroxy-2-oxo-propyl]-6,9-dimethyl-8-hydroxy-hexadec-2,7-dienoic acid methyl ester] (4a) and keto [(2E)-2-[(1R)-1-hydroxy-2-oxo-propyl]-6,9-dimethyl-8-oxo-hexadec-2-enoic acid methyl ester] (4b) tautomers. Compound 2 showed significant cytotoxicity against P-388 and HT-29 cancer cell lines. Also, 2 exhibited marginal activity against A549, 5 against P-388, and 1 against P-388, A549 and HT-29 cancer cell lines. Their structures were determined by spectroscopic analyses.

Six new compounds, including one nor-neolignan, dehydroxymethylailanthoidol (1), and five butanolides, litseakolide D (2), litseakolide E (3), litseakolide F (4), litseakolide G (5), and isolincomolide D (6), were isolated from the leaves of Litsea acutivena. Their structures were elucidated from spectral analyses. The butanolides (2-6) showed significant cytotoxic activity against P-388, A549, and HT-29 cell lines in vitro.

Three new quinoline alkaloids, 2-acetylevolitrine (1), 2-acetylpteleine (2), and semecarpifoline (3), along with 26 known compounds were isolated from the root bark of Melicope semecarpifolia. The structures of 1-3 were elucidated by means of spectral analysis. In addition, (2S)-(--)-7,8-dimethoxyplatydesmine (4), cis-(+)-7,8-dimethoxymyrtopsine (5), and (3R)-(--)-8,9-dimethoxygeibalansine (6) were isolated as new natural products. Several of these isolates were determined as exhibiting significant antiplatelet aggregation activities in vitro.

Aims: To further understand the effect of refractive error on the corneal dimensions and function., Methods: Corneal curvature, corneal thickness, and axial length measurements were performed, as well as specular microscopy and fluorophotometry, on patients with various refractive statuses. 216 subjects, mean age 22.2 (SD 4.2) years, were examined. Patients with previous contact lens wear history, external eye diseases, as well as previous ocular surgeries, were excluded., Results: The corneas were flatter in eyes with longer axial length (r = -0.22, p = 0.003). Eyes with more myopic spherical equivalent had longer axial length (r = -0.90, p <0.001) as well as less corneal endothelial density (r = 0.20, p = 0.037). Corneal endothelial density decreased in eyes with longer axial length (r = 0.24, p = 0.019); however, it correlated neither with corneal thickness (r = -0.06, p = 0.59) nor with corneal curvature (r = -0.07, p = 0.52). The corneas had a mean corneal thickness of 533 (SD 29) microm and were thinner in more myopic eyes (r = 0.16, p = 0.021). The corneas tended to be thinner in eyes with longer axial length. However, the correlation did not reach statistical significance (r = -0.11, p = 0.14). Besides, there was no significant correlation between the corneal thickness and the corneal curvature (r = -0.13, p = 0.093) and the endothelial permeability (r = 0.042, p = 0.69). The corneas with higher endothelial density had larger corneal transfer coefficient (r = 0.26, p = 0.024) and higher permeability to fluorescein molecules (r = 0.28, p = 0.014). Nevertheless, the corneal endothelial permeability did not correlate significantly with either the axial length (r = -0.18, p = 0.11) or the degree of myopia (r = 0.12, p = 0.26)., Conclusion: Changes in the anterior segments as the eyeball elongates in myopia progression included flatter corneal curvature, decreased corneal thickness, as well as decreased endothelial density. These factors should be considered in refractive surgery.

Further study on the chloroform-soluble portion of the root bark of Zanthoxylum schinifolium led to the isolation of eight new coumarins: methylschinilenol (1), hydroxyepoxycollinin I (2), 8-methoxyanisocoumarin H (3), hydroxyschininallylol (4), hydroxyepoxycollinin II (5), schinitrienin (6), schininallylone (7), and isoschinilenol (8), along with twenty-six known compounds including fourteen coumarins, and nine alkaloids. The structural elucidation was determined by spectroscopic data. Among the isolates, terpenyl-coumarins and furoquinolines were the active constituents with antiplatelet aggregation in vitro and collinin (10) showed significant anti-HBC DNA replication activity.

Four new cytotoxic neolignans, machilusol A (1), machilusol C (3), machilusol D (4), machilusol E (5) as well as two new inactive neolignans, machilusol B (2) and machilusol F (6), were isolated from the stem wood of Machilus obovatifolia. All structures were identified by means of spectroscopic analysis.

A p-hydroxyacetophenone-like derivative, (+)-gynunone, and a chromane, together with six known compounds were isolated from the CHCl3 fraction of the roots of Gynura elliptica. Their structures were determined by means of spectral analyses. Among the isolates, 6-acetyl-2,2-dimethylchroman-4-one and vanillin showed anti-platelet aggregation activity induced by arachidonic acid in vitro.

Examination on the wood of Formosan Toddalia asiatica led to the isolation of 30 compounds, including coumarins, alkaloids, a benzoquinone and an amine. Among the isolates, (+/-)-toddanin and (-)-isocoreximine are new compounds, while cyclohexylamine was isolated for the first time from nature. The structures of the compounds were elucidated from spectroscopic data and chemical evidence. Bioassay-guided fractionation led to the isolation of seven compounds showing strong anti-platelet aggregation activity in vitro.

Four additional neolignans, comprising obovatifol [(2S,3S)-2,3-dihydro-2- (3,4-dihydroxy-5-methoxyphenyl)-7-methoxy-3-methyl-5-trans-propenyl benzofuran], obovaten [2-(3,4-dihydroxy-5-methoxyphenyl)-7-methoxy-3- methyl-5-trans-propenyl benzofuran], perseal C [(2S,3R)-2,3-dihydro-2-(3,4-methylenedioxyphenyl)-5- formyl-3-hydroxymethyl-7-methoxy benzofuran] and perseal D [2-(3,4-dihydroxy-5-methoxyphenyl)-5-formyl-7- methoxy-3-methyl benzofuran] were isolated in a continuing study of the leaves of Persea obovatifolia. Obovatifol had been reported previously in a mass spectrometric analysis without any other spectroscopic data. Obovaten and perseals C and D are new compounds, bearing a C-1' formyl side-chain, instead of a propenyl group. Their structures were elucidated from spectroscopic data; they showed significant cytotoxic activities against P-388, KB16, A549 and HT-29 cancer cell lines in vitro.

A new dibenzylbutyrolactone lignan, (--)-6-hydroxyyatein, along with two new furanoid lignans, (--)-hernone [(2R,3S,4R)-(--)-3-hydroxymethyl -4-(3",4",5"-trimethoxybenzoyl)-2-(3,4-dimethoxyphenyl) tetrahydrofuran] and (--)-nymphone [(2R,3S,4R)-(--)-3-hydroxymethyl-4-(3",4",5"-trimethoxybenzoyl)-2- (3,4-methylenedioxyphenyl)tetrahydrofuran], have been isolated and characterized from the trunk bark of Formosan Hernandia nymphaeifolia. The structures of these compounds were determined by means of spectral analyses. These three lignans exhibited cytotoxic activities against P-388, KB16, A549 and HT-29 cell lines.

Two new aporphine alkaloids, (+)-N-hydroxyhernangerine (1) and N-formyldehydroovigerine (2) as minor bases, along with four known aporphines, (+)-magnoflorine, (+)-hernovine, (+)-N-methylhernovine, and (+)-laurotetanine, two known isoquinolones, thalifoline and northalifoline, and one benzylisoquinoline, (+)-reticuline, have been additionally isolated from the trunk bark of Hernandia nymphaeifolia. The structures of these compounds were elucidated by spectroscopic evidence. Six of the isolated compounds show significant cytotoxic activities (ED50 values < 1 microgram/ml) against P-388, KB16, A549, or HT-29 cell lines.

Three minor new dimeric aporphine alkaloids, oviisocorydine (1), ovihernangerine (2), and oxohernandaline (3), along with four known alkaloids, (+)-hernandaline, (+)-thallcarpine, (+)-N-methylovigerine, and N-methylcorydaldine, and five known lignans, (+)-epimagnolin, (+)-epiaschantin, (+)-epiyangambin, (-)-deoxypodophyllotoxin, and (-)-yatein, have been additionally isolated from the trunk bark of Hernandia nymphaeifolia. The structures of these compounds were elucidated by spectroscopic methods. Among forty-four isolates obtained till now, nine compounds, hernandonine (4), hernanymphine (5), demethylsonodione (6), (+)-ovigerine (7), (+)-N-methylovigerine (8), N-formyldehydroovigerine (9), 4-methoxyoxohernandaline (10), (-)-deoxypodophyllotoxin (11), and (-)-yatein (12) showed significant cytotoxic activities (ED50 values < 1 microgram/ml) against P-388, KB16, A549, and HT-29 cell lines.

Bioassay-guided fractionation led to the isolation of three indolopyridoquinazoline alkaloids, 1-hydroxyrutaecarpine, rutaecarpine, and 1-methoxyrutaecarpine as the active principles of antiplatelet aggregation in vitro, from the chloroform-soluble part of the fruit of Zanthoxylum integrifoliolum (Rutaceae). 1-Hydroxyrutaecarpine exhibited antiplatelet activity induced by AA and showed an IC50 value of ca. 1-2 micrograms/ml.

Four new khellactone esters, (-)-trans-3'-acetyl-4'-senecioylkhellactone, (+-)-cis-3'-acetyl-4'-tigloylkhellactone, (+-)-cis-4-tigloylkhellactone, (+)-trans-4'-tigloylkhellactone, together with 14 known coumarins, isoimperatorin, psoralen, bergapten, xanthotoxol, cnidilin, (-)-selinidin, (-)-deltoin, (+)-pteryxin, (+)-peucedanocoumarin III, xanthotoxin, imperatorin, (+)-marmesin, (+)-oxypeucedanin hydrate, (+)-peucedanol and three chromones, eugenin, (-)-hamaudol, (+)-visamminol, have been isolated from the root of Formosan Peucedanum japonicum. The structures of the new compounds were elucidated by spectral data. The identities of (+)-trans-3'-tigloyl-4'-acetylkhellactone, formerly reported as a new compound, and (+)-cis-3'-angeloyl-4'-acetyl-khellactone, with the known (+)-peucedanocoumarin III and (+)-pteryxin, respectively, are discussed. Among the isolates, seven compounds, eugenin, (-)-selinidin, (+)-pteryxin, imperatorin, bergapten, cnidilin and (+)-visamminol, show strong antiplatelet aggregation activity in vitro.

Three minor new p-quinonoid aporphine alkaloids, sonodione (1), demethylsonodione (2), and norsonodione (3), have been additionally isolated from the stem bark of Hernandia sonora. The structures of these compounds were elucidated by spectral analysis. Among the isolates obtained till now, five compounds, ovigerine (4), hernangerine (5), N-methylhernangerine (6), (+)-malekulatine (7), and isovanillin (8) showed moderate antiplatelet aggregation activity in vitro.

Six new coumarins, schinicoumarin, acetoxyaurapten, epoxycollinin, schininallylol, schinilenol and schinindiol, along with seven known coumarins, aurapten, collinin, epoxyaurapten, hydrangetin, umbelliferone, acetoxycollinin and aesculetin dimethyl ether, three known alkaloids, norchelerythrine, dictamnine and skimmianine, and two triterpenoids, beta-amyrin and friedelin, were isolated and characterized from the chloroform-soluble part of the bark of Zanthoxylum schinifolium. The structures of these compounds were elucidated by spectral analyses. Separation accompanied by bioassay-guided fractionation resulted in the isolation of seven compounds with strong inhibitory activity on platelet aggregation in vitro. These are schinicoumarin, acetoxyaurapten, schininallylol, aurapten, collinin, (-)-acetoxycollinin and dictamnine.

Two new benzo[c]phenanthridine alkaloids, 6-methyldihydrochelerythrine [1] and 6-methylnorchelerythrine [2], together with 23 known compounds, were isolated from the root bark of Zanthoxylum simulans. Structures were elucidated by spectral analysis. Among them, the pyranoquinoline alkaloids, zanthosimuline [3], and huajiaosimuline [4], exhibited cytotoxic activity. In addition, compound 4 showed significant antiplatelet aggregation activity and induced terminal differentiation with cultured HL-60 cells.

A screening test of antimicrobial activities for some of the isoquinoline alkaloids and their first and second Hofmann elimination products was conducted in this study. Results showed that (+)-actinodaphnine (1), (+)-N-Me-actinodaphnine (2), (+)-anonaine (17), (-)-xylopine (19) and (-)-N-Me-xylopine MeI (20), had the strongest inhibitory activities against three G(+) bacteria (Bacillus cereus, Micrococcus sp. and Staphylococcus aureus) MIC greater than or equal to 50 micrograms/ml). Whereas anhydroushinsunine (34), anhydroushinsunine MeI (35), ushinsunine isomethine (38), dicentrine methine (23), roemerine methine (26), dicentrine bismethine (29) and O-Me-armepavine methine (48) also had antibacterial effects against these same three G(+) bacteria (MIC = 50-300 micrograms/ml). However, only (+)-actinodaphnine (1) and roemerine methine (26) showed weak effects against two G(-) bacteria (Escherichia coli and Klebsiella pneumonia) (MIC = 300 micrograms/ml). (+)-Actinodaphnine(1), (+)-N-Me-actinodaphnine (2), (+)-anonaine (17), anhydroushinsunine (34), anhydroushinsunine MeI (35), ushinsunine isomethine (38), O-Me-armepavine methine (48) and O,O-di-Et-N-Me-coclaurine methine (49) had potent antifungal activities against Candida albicans, Cryptococcus neoformans and other Candida species (MIC = 62.5-1000 micrograms/ml).