Parinarioidins A-B,unprecedented flavonoids from the bark of Brosimum parinarioides Ducke

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Phytochemical and chemotaxonomic study on Ficus tsiangii Merr. ex Corner

Thirty-four compounds, including ten coumarins (1–10), thirteen flavonoids (11–23), three triterpenoid, one lignanoid (24), seven triterpenes (25–31) and three other compounds (32–34), were isolated from the stems of Ficus tsiangii Merr. ex Corner (F. tsiangii). Their structures were identified as xanthyletin (1), coumarin (2), umbelliferone (3), isoangenomalin (4), dihydroxanthyletin (5), scopoletin (6), nodakenetin (7), 6,7-dihydroxy-coumarin (8), 4'-O-β- glucopyranosyl-3'-hydroxy-nodakenetin (9), 6-carboxy-umbelliferone (10), 5,7,4'-trimethoxy- 3'-hydroxy-aurone (11), apigenin (12), naringenin (13), genistein (14), luteolin (15), prunetin (16), chrysoeriol (17), 5,6,7,-trihydroxy-4'-methoxy-flavone (18), eriodictyol (19), isocarthamidin (20), 5,7,2',4'-tetrahydroxyflavone (21), taxifolin (22), dihydro-kaempferol (23), syringeresinol (24), taraxerol (25), taraxerone (26), lupeolacetate (27), 3-acetoxy-12- oleanene-11-ketone (28), 3-acetoxy-lup-12,20(29)-diene (29), oleanic acid (30), ursolic acid (31), 3,4,5-trimethoxy phenyl-1-O-glucopyranoside (32), 8'-hydroxyabscisic acid glucoside (33) and adenosine (34). Among them, all compounds except 3, 14, 17, 25, 26, 30, 33 were isolated from the plant for the first time, and compounds 1, 4, 5, 8–11, 16, 18, 20, 23, 24, 32, 34 were firstly reported from the genus Ficus. The chemotaxonomic significance of these compounds was summarized as follows.     

Germination ecology of drupelets of the fig (Ficus carica L.)

Abiotic and biotic factors and their effects on germination of fig drupelets were studied. The drupelets germinated between 10^oC and 30^oC.Constant humidity was necessary for germination and frequent drying out of the substrate was unfavourable. Total darkness for the whole duration of the experiments had a slighly negative effect on germination. The fastest germination occurred at constant humidity and an alternating temperature of 20/30^oC with exposure to light for 8 hours (at the higher temperature) and to darkness for 16 hours (at the lower temperature).Natural or artificial removal of drupelets from the syconium guaranteed a high germination percentage, whereas no germination occurred in drupelets left inside the syconium. Hence birds and mammals act as dispersal agents and mediators of germination. As they eat pieces of fig syconium, they free the drupelets from the flesh, eliminating the effect of inhibitors and/or microenvironments with high osmotic pressure inside the syconium. These findings support the hypothesis that germination occurs in autumn or spring depending on the climatic zone in which the species grows.     

New prenylated dihydrochalcones from the leaves of Artocarpus elasticus

The leaves of Artocarpus elasticus collected in Thailand were investigated for chemical constituents. Four new prenylated dihydrochalcones named elastichalcones C, D, E, F (1, 3, 5, 6) together with elastichalcone B (2) and artocarpanone (4) were isolated. Their structures were determined from analysis of spectroscopic data. Elastichalcone C (1) exhibited good antibacterial activity and cytotoxicity.     

New diprenylated dihyrochalcones from leaves of Artocarpus elasticus

Two new diprenylated dihydrochalcones, elastichalcone A 1 and elastichalcone B 2 and three known compounds were isolated from the leaves of Artocarpus elasticus. Their structures were determined by various spectroscopic techniques (UV, IR, MS, 1D-NMR and 2D-NMR). Elastichalcone B 2 and a known compound exhibited good free radical scavenging activity with IC₅₀ values of 11.30 and 11.89 μg/ml, respectively.     

Biogenesis of linear O-alkylfuranocoumarins: A new pathway involving 5-hydroxymarmesin

adioactivity from [³H] 5-hydroxymarmesin was incorporated into 5-methoxypsoralen by administration to leaves of Ficus carica and cut ends of Ruta graveolens. No other furanocoumarins were labelled. Trapping experiments, in which [³H]marmesin together with 5-hydroxymarmesin was administered to fig leaves and to cut ends of rue, provided good evidence that 5-hydroxymarmesin is formed by hydroxylation of marmesin. These results, together with those obtained previously with 8-hydroxymarmesin demonstrate that, in addition to the pathway which involves the hydroxylation of psoralen, the O-alkylfuranocoumarins are also formed by a pathway which involves the hydroxylation of marmesin.     

A new species of ficus (moraceae) of uncertain provenance

A new species,Ficus salicaria, is described from material cultivated as ornamental. The material is of uncertain provenance but was probably collected originally in Guyana.