Coumarinolignans from the Root of Formosan Antidesma pentandrum var. barbatum

Four new coumarinolignans, antidesmanin A (=7‐(1,1‐dimethylallyl)‐2,3‐dihydro‐3‐(4‐hydroxy‐3,5‐dimethoxyphenyl)‐10‐methoxy‐2‐methyl‐6H‐1,4,5‐trioxaphenanthren‐6‐one; 1 ), antidesmanin B (=3,7‐bis(1,1‐dimethylallyl)‐2,3‐dihydro‐2‐(4‐hydroxy‐3‐methoxyphenyl)‐10‐methoxy‐6H‐1,4,5‐trioxaphenanthren‐6‐one; 2 ), antidesmanin C (=2,7‐bis‐(1,1‐dimethylallyl)‐2,3‐dihydro‐3‐(4‐hydroxy‐3‐methoxyphenyl)‐10‐methoxy‐6H‐1,4,5‐trioxaphenanthren‐6‐one; 3 ) and antidesmanin D (=2‐(3,4‐dihydroxyphenyl)‐3,7‐bis(1,1‐dimethylallyl)‐2,3‐dihydroxy‐10‐methoxy‐6H‐1,4,5‐trioxaphenanthren‐6‐one or 3‐(3,4‐dihydroxyphenyl)‐2,7‐bis(1,1‐dimethylallyl)‐2,3‐dihydro‐10‐methoxy‐6H‐1,4,5‐trioxaphenanthren‐6‐one; 4 ) have been isolated from the root of the Formosan Antidesma pentandrum var. barbatum. The structures of these new compounds were elucidated by spectroscopic data. Compounds 1 – 3 exhibited marginal cytotoxicity against MCF‐7 (breast) and SF‐268 (CNS) cancer cell lines in vitro.     

Bioactive Components from the Mycelium of Antrodia Salmonea

Three new compounds, 2,4‐dimethoxy‐6‐methylbenzene‐1,3‐diol ( 1 ), salmoquinone ( 2 ), and 3‐(4‐hydroxyphenyl)‐4‐isobutyl‐1H‐pyrrole‐2,5‐dione ( 3 ), together with six known compounds, 2‐methoxy‐6‐methyl‐p‐benzoquinone ( 4 ), 2,3‐dimethoxy‐5‐methyl‐p‐benzoquinone ( 5 ), 2‐hydroxy‐5‐methoxy‐3‐methyl‐p‐benzoquinone ( 6 ), eburcoic acid ( 7 ), fomefficinic acid C ( 8 ), and a pyrroledione ( 9 ), were isolated from the mycelium of Antrodia salmonea. The structures of these compounds were elucidated by spectrometric analyses including IR, NMR, and MS. Among these compounds, 4 and 5 exhibited cytotoxicity against KB, HepG2, and H2058 cell lines.     

Three New Neolignans from the Aril of Myristica fragrans

Three new neolignans, named 1‐deoxycarinatone ( 1 ), isodihydrocarinatidin ( 2 ), and isolicarin A ( 3 ), together with the known neolignan (+)‐dehydrodiisoeugenol ( 4 ), were isolated from mace (the aril of Myristica fragrans Houtt .). Their structures were elucidated as 2‐[(1S)‐2‐(4‐hydroxy‐3‐methoxyphenyl)‐1‐methylethyl]‐6‐methoxy‐4‐(prop‐2‐enyl)phenol ( 1 ), 4‐[(2R,3R)‐2,3‐dihydro‐7‐methoxy‐3‐methyl‐5‐(prop‐2‐enyl)benzofuran‐2‐yl]‐2‐methoxyphenol ( 2 ), and 4‐{(2S,3R)‐2,3‐dihydro‐7‐methoxy‐3‐methyl‐5‐[(1E)‐prop‐1‐enyl]benzofuran‐2‐yl}‐2‐methoxyphenol ( 3 ) on the basis of spectroscopic data.     

A Guaianolide Sesquiterpene,a Chromenone,and a Flavanone from Ligularia macrophylla

Three new compounds, (5β,9β)‐guaia‐6,10(14)‐dien‐9‐ol (=rel‐(1R,3aS,5R,8aR)‐1,2,3,3a,4,5,6,8a‐octahydro‐1‐methyl‐4‐methylene‐7‐(1‐methylethyl)azulen‐5‐ol; 1 ), 6‐acetyl‐8‐methoxy‐2,3‐dimethylchromen‐4‐one (=6‐acetyl‐8‐methoxy‐2,3‐dimethyl‐4H‐1‐benzopyran‐4‐one; 2 ), and (2S)‐3′‐hydroxy‐5′,7‐dimethoxyflavanone (=(2S)‐2,3‐dihydro‐2‐(3‐hydroxy‐5‐methoxyphenyl)‐7‐methoxy‐4H‐1‐benzopyran‐4‐one; 3 ) were isolated from the roots and rhizomes of Ligularia macrophylla, together with seven known compounds. Their structures and configurations were elucidated by spectroscopic methods, including 2D‐NMR techniques.     

Two New Citrinin Dimers from a Volcano Ash‐Derived Fungus,Penicillium citrinum HGY1‐5

Two new citrinin dimers, penidicitrinin A ((2R,3S,5aS,9R,10S,12aR,12bR)‐2,3,5a,6,9,10,12a,12b‐octahydro‐7,12a‐dihydroxy‐12b‐methoxy‐2,3,4,9,10,11‐hexamethyl‐5H‐difuro[2,3‐b : 2′,3′‐h]xanthen‐5‐one; 1 ) and penidicitrinin B ((1S,3R,4S)‐1‐{2,6‐dihydroxy‐4‐[(1S,2R)‐2‐hydroxy‐1‐methylpropyl]‐3‐methylphenyl}‐3,4‐dihydro‐3,4,5‐trimethyl‐1H‐2‐benzopyran‐6,8‐diol; 2 ), together with three known citrinin monomers were isolated from a volcano ash‐derived fungus, Penicillium citrinum HGY1‐5. Their structures were established by spectroscopic methods, and they showed no cytotoxicity against two tumor cell lines.     

New Cytotoxic Laurene‐, Cuparene‐, and Laurokamurene‐Type Sesquiterpenes from the Red Alga Laurencia obtusa

Three new sesquiterpene alcohols, laur‐2‐ene‐3,12‐diol ( 1 ), cuparene‐3,12‐diol ( 2 ), and 8,11‐dihydro‐1‐methoxylaurokamuren‐12‐ol ( 3 ), along with one known diterpene, kahukuen‐10‐ol ( 4 ) have been isolated from the organic extract of the red alga Laurencia obtusa. The chemical structures were elucidated on the basis of spectroscopic analysis. The cytotoxicity of the isolated compounds were evaluated against three cancer cell lines, i.e., KB, HepG2, and MCF‐7. Compound 4 exhibited a wide range of cytotoxic activity against KB, HepG2, and MCF‐7 cell lines with IC₅₀ of 0.100, 0.057, and 0.054 μm, respectively. In addition, 1 showed moderate activities towards KB and MCF‐7 cell lines with IC₅₀ values of 0.171 and 0.184 μM , respectively and 2 exhibited a moderate activity against KB cell line at a concentration of 0.213 μg/ml. On the other hand, compound 3 exhibited no cytotoxic activity against any of the three cell lines.     

Lignans from Phryma leptostachya L.

Three new lignans, haedoxan J ( 1 ), phrymarolin III ( 2 ), and phrymarolin IV ( 3 ), as well as eight known lignans, leptostachyol acetate, haedoxan A, 1‐(4,6‐dimethoxy‐1,3‐benzodioxol‐5‐yl)dihydro‐4‐(6‐methoxy‐1,3‐benzodioxol‐5‐yl)‐1H,3H‐furo[3,4‐c]furan‐3a(4H)‐yl acetate, 4‐(4,6‐dimethoxy‐1,3‐benzodioxol‐5‐yl)dihydro‐1‐(4‐methoxy‐1,3‐benzodioxol‐5‐yl)‐1H,3H‐furo[3,4‐c]furan‐3a(4H)‐yl acetate, 4‐[(4,6‐dimethoxy‐1,3‐benzodioxol‐5‐yl)oxy]dihydro‐1‐(6‐methoxy‐1,3‐benzodioxol‐5‐yl)‐1H,3H‐furo[3,4‐c]furan‐3a(4H)‐yl acetate, leptostachyol acetate C, 4‐(4,6‐dimethoxy‐1,3‐benzodioxol‐5‐yl)dihydro‐1‐(6‐methoxy‐1,3‐benzodioxol‐5‐yl)‐1H,3H‐furo[3,4‐c]furan‐3a(4H)‐yl acetate, and phrymarin II, were isolated from the plant Phryma leptostachya L. The structures of the new compounds were elucidated by analyzing their spectroscopic data and comparing with data reported in the literature.     

New α‐Glucosidase Inhibitors from the Mongolian Medicinal Plant Ferula mongolica

The four new and four known sesquiterpenoid derivatives 1 – 4 and 5 – 8 , respectively, were isolated from the air‐dried roots of Ferula mongolica. The structures of these compounds were determined by spectroscopic methods and found to be rel‐(2R,3R)‐2‐[(3E)‐4,8‐dimethylnona‐3,7‐dienyl]‐3,4‐dihydro‐3,8‐dihydroxy‐2‐methyl‐2H,5H‐pyrano[2,3‐b][1]benzopyran‐5‐one ( 1 ), rel‐(2R,3R)‐2‐[(3E)‐4,8‐dimethylnona‐3,7‐dienyl]‐2,3‐dihydro‐7‐hydroxy‐2,3‐dimethyl‐4H‐furo[2,3‐b][1]benzopyran‐4‐one ( 2 ), rel‐(2R,3R)‐2‐[(3E)‐4,8‐dimethylnona‐3,7‐dienyl]‐2,3‐dihydro‐7‐hydroxy‐2,3‐dimethyl‐4H‐furo[3,2‐c][1]benzopyran‐4‐one ( 3 ), rel‐(2R,3R)‐2‐[(3E)‐4,8‐dimethylnona‐3,7‐dienyl]‐2,3‐dihydro‐7‐methoxy‐2,3‐dimethyl‐4H‐furo[3,2‐c][1]benzopyran‐4‐one ( 4 ), (4E,8E)‐1‐(2‐hydroxy‐4‐methoxyphenyl)‐5,9,13‐trimethyltetradeca‐4,8,12‐trien‐1‐one ( 5 ), the rel‐(2R,3S) diastereoisomer 6 of 2 , the rel‐(2R,3S) diastereoisomer 7 of 4 , and (4E,8E)‐1‐(2,4‐dihydroxyphenyl)‐5,9,13‐trimethyltetradeca‐4,8,12‐trien‐1‐one ( 8 ). These compounds were tested as inhibitors against the enzyme α‐glucosidase. The compounds 1 – 6 and 8 exhibited significant inhibitory activity and, therefore, represent a new class of α‐glucosidase inhibitors.     

A Novel Norlignan and a Novel Phenylpropanoid from Peperomia tetraphylla

A novel cyclobutane‐type norlignan, peperotetraphin (=methyl rel‐(1R,2S,3S)‐2,3‐bis(7‐methoxy‐1,3‐benzodioxol‐5‐yl)cyclobutanecarboxylate; 1 ), and a novel phenylpropanoid, i.e., methyl (2E)‐3‐(7‐methoxy‐1,3‐benzodioxol‐5‐yl)prop‐2‐enoate ( 2 ), along with three known compounds, α‐asarone (=1,2,4‐trimethoxy‐5‐[(1E)‐prop‐1‐en‐1‐yl]benzene), vanillic acid (=4‐hydroxy‐3‐methoxybenzoic acid), and veratric acid (=3,4‐dimethoxybenzoic acid), were isolated from the EtOH extract of the whole plant of Peperomia tetraphylla. Their structures were determined by spectroscopic methods, especially 1D‐ and 2D‐NMR techniques. This is the first report of naturally occurring cyclobutane‐type norlignans.     

Synthesis and Cytotoxic Activity of Novel Pyrazoline Derivatives against Human Lung Tumor Cell Line (A549)

In the present investigation, a series of 5‐(‐4‐(substituted)phenyl)‐3‐(4‐hydroxy‐3‐methylphenyl)‐4,5‐dihydro‐1H‐1‐pyrazolyl‐2‐toluidino methane thione and 5‐(substituted)phenyl‐3‐(4‐hydroxy‐3‐methylphenyl)‐4,5‐dihydro‐1H‐1‐pyrazolyl‐2‐methoxy anilino methane thiones were synthesized and were examined against human lung tumor cell line (A549) in vitro using the MTT assay system. Among those tested, 5‐(4‐flurophenyl)‐3‐(4‐hydroxy‐3‐methylphenyl)‐4,5‐dihydro‐1H‐1‐pyrazolyl‐2‐toluidino methane thione & 5‐(4‐chlorophenyl)‐3‐(4‐hydroxy‐3‐methylphenyl)‐4,5‐dihydro‐1H‐1‐pyrazolyl‐2‐methoxy anilino methane thione showed more potent cytotoxicity against human lung tumor cell line (A549) than the other synthesized compounds.     

Sydnones as Masked Hydrazines for the Synthesis of 4‐Arylazo‐1,2‐dihydro‐pyrazol‐3‐one Derivatives

A simple and convenient one‐pot synthesis of 4‐(4‐chlorophenylazo)‐5‐methyl‐2‐aryl‐1,2‐dihydro‐pyrazol‐3‐ones (4a–j) has been carried out from 3‐arylsydnones (3a–j) by reaction with 2‐(4‐chlorophenyl)‐hydrazono‐3‐oxo‐butyric acid ethyl ester (2b). The 3‐arylsydnones are used as masked hydrazines in this reaction. Similarly, the 4‐arylazo‐2‐(7‐hydroxy‐4‐methyl‐2‐oxo‐2H‐chromen‐8‐ylmethyl)‐5‐methyl‐1,2‐dihydro‐pyrazol‐3‐ones (7a–j) were synthesized from 3‐[(7‐acetoxy‐4‐methyl‐8‐methylene)coumaryl]sydnone (5). All the newly synthesized compounds exhibited antimicrobial activity greater than the reference drugs used.     

Chemical and Cytotoxic Constituents from the Stem of Machilus zuihoensis

Five new compounds, including a novel lactone, machilactone (=rel‐(2R,3aR,6E,6aS)‐2‐heptadecyl‐3a‐methyl‐6‐octadecylidene‐6,6a‐dihydrofuro[2,3‐d][1,3]dioxol‐5(3aH)‐one; 1 ), a new sesquiterpene, 3,4‐dihydroxy‐β‐bisabolol (=rel‐(1R,2S,4R)‐1‐[(1R)‐1,5‐dimethylhex‐4‐enyl]‐1‐methylcyclohexane‐1,2,4‐triol; 2 ), a new secobutyrolactone, methyl (2E)‐2‐(1‐hydroxy‐2‐oxopropyl)eicos‐2‐enoate ( 3 ), two new butyrolactones, machicolide A ( 4 ) and machicolide B ( 5 ) (=3E,4R,5R)‐ and (3Z,4R,5R)‐4,5‐dihydro‐4‐hydroxy‐5‐methoxy‐5‐methyl‐3‐octadecylidenefuran‐2(3H)‐one, resp.) as a mixture, together with known caryophyllene oxide (=4,12,12‐trimethyl‐9‐methylene‐5‐oxatricyclo[8.2.0.0^4,6]dodecane), hexacosane, tetracosanoic acid, isomahubanolide‐23 (=(3E,4R)‐4,5‐dihydro‐4‐hydroxy‐5‐methylidene‐3‐octadecylidenefuran‐2(3H)‐one), and β‐bisabolol (=(1S)‐1‐[(1S)‐1,5‐dimethylhex‐4‐enyl]‐4‐methylcyclohex‐3‐en‐1‐ol) were isolated from the stem wood of Machilus zuihoensis. The structures of these compounds were established by spectroscopic studies. The eicos‐2‐enoate ( 3 ) and β‐bisabolol exhibited marginal cytotoxicity against NUGC and HONE‐1 cancer cell lines in vitro.     

Complete structural and spectral assignment of oxoisoaporphines by HMQC and HMBC experiments

The oxoisoaporphines 2,3‐dihydro‐7H‐dibenzo[de,h]quinolin‐7‐one, 2,3‐dihydro‐5‐methoxy‐7H‐dibenzo [de,h] quinolin‐7‐one, 5‐methoxy‐6‐hydroxy‐2,3‐dihydro‐7H‐dibenzo[de,h]quinolin‐7‐one, 5,6‐dimethoxy‐2,3‐dihydro‐7H‐dibenzo[de,h]quinolin‐7‐one and 5,6‐methylenedi‐oxy‐2,3‐dihydro‐7H‐dibenzo[de,h]quinolin‐7‐one were prepared by cyclization of phenylethylaminophthalides with polyphosphoric acid or by treating 1‐(2‐carboxyphenyl)‐3,4‐dihydroisoquinoline hydrochloride with sulfuric acid at 0 °C. The structures were confirmed and ¹H and ¹³C NMR spectra were completely assigned using a combination of one‐ and two‐dimensional NMR techniques. Copyright © 2003 John Wiley & Sons, Ltd.     

Synthesis,Characterization, and Cytotoxicity Evaluation of Some New Benzo[f]coumarin Derivatives

Interaction of 2‐(bromoacetyl)‐3H‐benzo[f]coumarin ( 1 ) with salicylaldehyde afforded 2‐(2‐oxo‐2‐(3H‐benzo[f]coumarin‐2‐yl)ethoxy)benzaldehyde ( 2 ) which underwent self‐condensation in refluxing dimethylformamide (DMF) to afford 2‐(2‐benzofuroyl)‐3H‐benzo[f]coumarin (3). Treatment of 1 with o‐aminothiophenol ( 4 ) gave 2‐(2‐((2‐aminophenyl)thio)acetyl)‐3H‐benzo[f]coumarin (5) . Refluxing of 5 in DMF led to formation of 2‐(4H‐[1,4]‐benzothiazin‐3‐yl)‐3H‐benzo[f]coumarin (6). Treatment of 1 with aryl amines 7a–d in boiling DMF gave 1‐aryl‐3‐hydroxybenzo[5,6]chromeno[4,3‐b]pyrrol‐4(1H)‐one ( 10a–d ) . Condensation of 11 with o‐phenylenediamine gave 2‐(2‐methyl‐2,3‐dihydro‐1H‐benzimidazol‐2‐yl)‐3H‐benzo[f]coumarin ( 12 ). Interaction of 2‐acetyl‐3H‐benzo[f]coumarin ( 11 ) with arylidene malonononitrile gave 4‐hydroxy‐2‐(3H‐benzo[f]coumarin‐2‐yl)‐5H‐dibenzo[c,f]chromen‐5‐one ( 16) . All reaction products were characterized by analytical and spectral data. Novel compounds bioactivity as antitumor were examined for in vitro cytotoxicity against HepG‐2 and MCF‐7.     

Synthesis,crystal structure and activity evaluation of novel 3,4‐dihydro‐1‐benzoxepin‐5(2H)‐one derivatives as protein–tyrosine kinase (PTK) inhibitors

Four new 3,4‐dihydro‐1‐benzoxepin‐5(2H )‐one derivatives, namely (E )‐4‐(5‐bromo‐2‐hydroxybenzylidene)‐6,8‐dimethoxy‐3,4‐dihydrobenzo[b ]oxepin‐5(2H )‐one, ( 7 ), (E )‐4‐[(E )‐3‐(5‐bromo‐2‐hydroxyphenyl)allylidene]‐6,8‐dimethoxy‐3,4‐dihydrobenzo[b ]oxepin‐5(2H )‐one, ( 8 ), (E )‐4‐(5‐bromo‐2‐hydroxybenzylidene)‐6‐hydroxy‐8‐methoxy‐3,4‐dihydrobenzo[b ]oxepin‐5(2H )‐one, C₁₈H₁₅BrO₅, ( 9 ), and (E )‐4‐[(E )‐3‐(5‐bromo‐2‐hydroxyphenyl)allylidene]‐6‐hydroxy‐8‐methoxy‐3,4‐dihydrobenzo[b ]oxepin‐5(2H )‐one, ( 10 ), have been synthesized and characterized by FT–IR, NMR and MS. The structure of ( 9 ) was confirmed by single‐crystal X‐ray diffraction. Crystal structure analysis shows that molecules of ( 9 ) are connected into a one‐dimensional chain in the [010] direction through classical hydrogen bonds and these chains are further extended into a three‐dimensional network via C—H…O interactions. The inhibitory activities of these compounds against protein–tyrosine kinases (PTKs) show that 6‐hydroxy‐substituted compounds ( 9 ) and ( 10 ) are more effective for inhibiting ErbB1 and ErbB2 than are 6‐methoxy‐substituted compounds ( 7 ) and ( 8 ). This may be because ( 9 ) and ( 10 ) could effectively bind to the active pockets of the protein through intermolecular interactions.     

New Phenylphenalene Derivatives from Water Hyacinth (Eichhornia crassipes)

Water hyacinth (Eichhornia crassipes) is a cause of great concern in terms of environmental and agricultural impacts in many parts of the world. Phytochemical investigation of water hyacinth led to the isolation of six new phenylphenalenes, 2,3‐dihydro‐3,9‐dihydroxy‐5‐methoxy‐4‐phenyl‐1H‐phenalen‐1‐one ( 1 ), 2,3‐dihydro‐8‐methoxy‐9‐phenyl‐1H‐phenalene‐1,4‐diol ( 2 ), 2,3‐dihydro‐4,8‐dimethoxy‐9‐phenyl‐1H‐phenalen‐1‐ol ( 3 ), 2,3‐dihydro‐9‐(4‐hydroxyphenyl)‐8‐methoxy‐1H‐phenalene‐1,4‐diol ( 4 ), 2,6‐dimethoxy‐9‐phenyl‐1H‐phenalen‐1‐one ( 5 ), and 7‐(4‐hydroxyphenyl)‐5,6‐dimethoxy‐1H‐phenalen‐1‐one ( 6 ), together with the four known compounds 7 – 10 . Their structures were elucidated by spectrometric methods including 1D‐ and 2D‐NMR, and MS analysis. These compounds may be involved in allelopathic interactions of water hyacinth with neighboring plants.     

Rubriflorin A and B,Two Novel Partially Saturated Dibenzocyclooctene Lignans from Schisandra rubriflora

From the stems of Schisandra rubriflora, two novel partially saturated dibenzocyclooctene lignans, named rubriflorin A ( 1 ) and B ( 6 ), as well as the seven known partially saturated dibenzocyclooctene lignans kadsumarin A ( 2 ), kadsurin ( 3 ), heteroclitin B ( 4 ), heteroclitin C ( 5 ), heteroclitin D ( 7 ), interiorin ( 8 ), and interiorin B ( 9 ) were isolated. The structures of the new compounds 1 and 6 were established on the basis of spectral analysis as (5R,6S,7R,8R,13aS)‐8‐(acetyloxy)‐5,6,7,8‐tetrahydro‐1,2,3,13‐tetramethoxy‐6,7‐dimethylbenz([3,4]cycloocta[1,2‐f][1,3]benzodioxol‐5‐yl (2Z)‐2‐methylbut‐2‐enoate and (6R,7R,12aS)‐7,8‐dihydro‐12‐hydroxy‐1,2,3,10,11‐pentamethoxy‐6,7‐dimethyl‐6H‐dibenzo[a,c]cycloocten‐5‐one, respectively.     

Two New Naphthoquinone Derivatives from Lysionotus pauciflorus

Two new naphthoquinones, (2R)‐6,8‐dihydroxy‐α‐dunnione ( 1 ), 6,8‐dihydroxy‐2,7‐dimethoxy‐3‐(1,1‐dimethylprop‐2‐enyl)‐1,4‐naphthoquinone ( 2 ), together with three known compounds, (2R)‐6,8‐dihydroxy‐7‐methoxy‐α‐dunnione ( 3 ), nevadensin ( 4 ), and lysioside C ( 5 ), were isolated from the whole plant of Lysionotus pauciflorus. Their structures were established by spectroscopic methods. Hydroxylated naphthoquinones are reported to occur in a Lysionotus species for the first time. The cytotoxic activities of compounds 1 – 3 were evaluated in vitro against a panel of tumor cell lines.     

Flavonoids from the Resin of Dracaena cochinchinensis

Chemical investigation of the red herbal resin of Dracaena cochinchinensis resulted in the isolation of three new configurationally isomeric flavonoids: 6,4′‐dihydroxy‐7‐methoxy‐8‐methylflavane (=3,4‐dihydro‐2‐(4‐hydroxyphenyl)‐7‐methoxy‐8‐methyl‐2H‐[1]benzopyran‐6‐ol; 1 ), 5,4′‐dihydroxy‐7‐methoxy‐6‐methylflavane (=3,4‐dihydro‐2‐(4‐hydroxyphenyl)‐7‐methoxy‐6‐methyl‐2H‐[1]benzopyran‐5‐ol; 2 ), and 7,4′‐dihydroxy‐5‐ methoxyhomoisoflavane (=3,4‐dihydro‐3‐[(4‐hydroxyphenyl)methyl]‐5‐methoxy‐2H‐[1]benzopyran‐7‐ol; 3 ). Their structures were identified by means of detailed spectral analysis. In addition, thirteen known compounds were isolated from D. cochinchinensis: 7‐hydroxy‐4′‐methoxyflavane ( 4 ), 2,4,6‐trimethoxy‐4′‐hydroxydihydrochalcone ( 5 ), 2,4‐dimethoxy‐4′‐hydroxydihydrochalcone ( 6 ), 7,8‐(methylenedioxy)‐4′‐hydroxyhomoisoflavane ( 7 ), 4′,7‐dihydroxy‐8‐methylflavane ( 8 ), 2,6‐dimethoxy‐4,4′‐dihydroxydihydrochalcone ( 9 ), 2‐methoxy‐4,4′‐dihydroxydihydrochalcone ( 10 ), 7‐methoxy‐6,4′‐dihydroxyhomoisoflavane ( 11 ), 2‐methoxy‐4,4′‐dihydroxychalcone ( 12 ), 4′,7‐dihydroxyflavane ( 13 ), 7,4′‐dihydroxyhomoisoflavane ( 14 ), 7,4′‐dihydroxyhomoisoflavone ( 15 ), and 7,4′‐dihydroxyflavone ( 16 ). Compounds 7, 8, 9, 14 , and 15 have been isolated for the first time from this type of herbal source.     

Complete 1H and 13C NMR spectral assignment of hydrogenated oxoisoaporphine derivatives

2,3,8,9,10,11‐Hexahydro‐7H‐dibenzo[de,h]quinolin‐7‐one, 5‐methoxy‐2,3,8,9,10,11‐hexahydro‐7H‐dibenzo[de,h]quinolin‐7‐one, 5‐methoxy‐6‐hydroxy‐1,2,3,7a,8,9,10,11,11a,11b‐decahydro‐7H‐dibenzo[de,h]quinolin‐7‐one, 5‐methoxy‐5,6,8,9,10,11‐hexahydro‐4H‐dibenzo[de,h]quinolin‐7‐ol, 5,6,8,9,10,11‐hexahydro‐4H‐dibenzo[de,h]quinolin‐7‐ol and 5,6‐dihydro‐4H‐dibenzo[de,h]quinolin‐7‐ol were prepared by catalytic hydrogenation of oxoisoaporphines or their 2,3‐dihydro derivatives over PtO₂ in acetic acid under mild conditions. Their structures were confirmed and ¹H and ¹³C NMR spectra were completely assigned using a combination of one‐ and two‐dimensional NMR techniques. Copyright © 2003 John Wiley & Sons, Ltd.