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Phytochemical investigation of Hylodendron gabunensis resulted in the isolation of two new glyceride derivatives, hyloglyceride (1) and hylodiglyceride (2). The structures of the two new compounds were determined by comprehensive analysis of their 1D and 2D NMR spectroscopic, and HREIMS data. One known compound was also isolated and identified as β-sitosterol.

Phytochemical investigation of Nepeta distans Raul resulted in the isolation of a new phenolic compound, nepatanol (1), and eight known compounds, markhamioside F, netidiol, nepedinol, thymoquinone, eugenol, oleanolic acid, ursolic acid, and β-sitosterol, which have been isolated for the first time from this source. Structures of all the isolates were established on the basis of MS, and 1D and 2D NMR spectral data and by comparison with reported data.

Pycnanthus anglonensis is known for its medicinal value. This paper deals with a phytochemical investigation of this species, from which pycnangloside (1), a new cerebroside has been isolated. Its structure was determined by comprehensive analyses of its 1D and 2D NMR spectroscopic, and ESI mass spectrometric data. Four known compounds were also isolated and identified as biochanin A, formonentin, β-sitosterol, and β-sitosterol glucopyranoside.

Eight compounds were isolated from the stem bark of the plant Afraegle paniculata. One of them, a dimethyl ether of S-trans-marmin (1), is reported as a new natural product. The structures were determined by comprehensive analyses of their 1D and 2D NMR spectroscopic and HREIMS data. The remaining seven known compounds, identified by comparing their spectroscopic data with those reported in the literature, were S-trans-marmin (2), psoralene (3), bergaptene (4), imperatorin (5), 2-(4-hydroxy-3,5-dimethoxyphenyl)-3-hydroxymethyl-2,3-dihydro-1,4,5-trioxaphenanthren-6-one (6), xanthoxyletin (7), and β-sitosterol glucopyranoside. Preliminary studies indicated that compounds 2, 3, 5, and 7 showed potent antibacterial, fungicidal, and algicidal properties, while 6 showed only moderate algicidal property.

Four compounds were isolated from the stem bark of Antiaris africana. One of them, a γ-lactone named antialactone (1a), is reported for the first time as a natural product. The structures were determined by comprehensive analyses of their 1D and 2D NMR spectra and EI MS data. The absolute configuration of antialactone acetate (1b) was established by TDDFT CD calculations and comparison with measured CD spectra. The remaining three known compounds were identified, by comparing their spectroscopic data with those reported in the literature, as lichenxanthone, β-sitosterol, and betulinic acid.

A unique highly substituted chromone dimer, named exochromone (la), in addition to the known steroids ergosterol (2) and 5a,8a-epidioxyergosterol (3) were isolated from endophytic fungus Exophiala sp. The structure of the new compound was elucidated on the basis of spectroscopic data. Preliminary studies showed that exochromone is antifungal and antialgal against Microbotryum violaceum and Chlorella fusca, respectively.

Objective To evaluate the antimicrobial potential of different extracts of the endophytic fungus Phoma sp. and the tentative identification of their active constituents. Methods The extract and compounds were screened for antimicrobial activity using the Agar Well Diffusion Method. Four compounds were purified using column chromatography and their structures were assigned using 1 H and 13 C NMR spectra, DEPT, 2D COSY, HMQC and HMBC experiments. Results The ethyl acetate fraction of Phoma sp. showed good antifungal, antibacterial, and algicidal properties. One new dihydrofuran derivative, named phomafuranol (1), together with three known compounds, phomalacton (2), (3R)-5-hydroxymellein (3) and emodin (4) were isolated from the ethyl acetate fraction of Phoma sp. Preliminary studies indicated that phomalacton (2) displayed strong antibacterial, good antifungal and antialgal activities. Similarly (3R)-5-hydroxymellein (3) and emodin (4) showed good antifungal, antibacterial and algicidal properties. Conclusions Antimicrobial activities of the ethyl acetate fraction of the endophytic fungus Phoma sp. and isolated compounds clearly demonstrate that Phoma sp. and its active compounds represent a great potential for the food, cosmetic and pharmaceutical industries.

One new diterpene ester with a tricyclic lathyrane-or myrsinol-type skeleton has been isolated from Euphorbia decipiens Boiss.&Buhse. In addition to one new, the known constituents β-amyrin, β-amyrin acetate, methyl (2,4-dihydroxy-3-formyl-6-methoxy) phenyl ketone (2), and 1,1-bis (2,6-dihydroxy-3-acetyl-4-methoxyphenyl) methane (3) have been isolated from the same source. The structure elucidation of the isolated compounds was based primarily on 1D and 2D-NMR analysis, including COSY, HMQC, HMBC and NOESY correlations. Compound 1 showed inhibitory activity against prolyl endopeptidase, and also analgesic activity

A new tricyclic clerodane-type diterpene, nepetolide (1), has been isolated from Nepeta suavis along with three known compounds namely β -sitosterol, stigmasterol, and ursolic acid. The structure elucidation of the isolated compounds was based primarily on two-dimensional (2D)-NMR techniques including correlation spectroscopy (COSY), heteronuclear multiple quantum coherence (HMQC), and heteronuclear multiple bond correlation (HMBC) experiments.

Melicimides A (1) and B (2), two new ceremides have been isolated from Melicia excelsa ( Moraceae). The structures of the new compounds were determined by comprehensive analyses of their 1D ( 1H and 13C NMR), 2D NMR (including COSY, HMQC, and HMBC) and ESIMS spectral data. A known compound viz., β-sitosterol has also been identified.

The leaf and bark extracts of Salix subserrata showed promising antibacterial, antifungal, and antialgal activities. The bio-guided study of the chemical constituents of the bark and leaves of Salixsubserrata (Salicaceae) has resulted in the isolation and characterization of eight compounds. These six compounds were identified as (+) catechin ( 1), 1,2-benzenedicarboxylic acid, bis (2-ethylhexyl) ester ( 2), saligenin (3), methyl 1-hydroxy-6-oxocyclohex-2-enecarboxylate (4), catechol (5), propyl acetate ( 6), β-sitosterol (7), and β-sitosterol glucopyranoside ( 8), were isolated for the first time from Salixsubserrata. The above compounds were individually identified by spectroscopic analyses and comparisons with reported data . Preliminary studies indicated that compound 1, mixture of compounds 3/4, and 7 showed good antibacterial, fungicidal, and algicidal properties.

The redox behavior of a novel quinoxaline carboxylic acid derivative, 6-(1-hydroxynaphthalen-2-yl) benzo[f]quinoxaline-2-carboxylic acid (HBQCA) was studied at the surface of glassy carbon electrode in a wide pH range using modern electrochemical techniques. Cyclic, square wave and differential pulse voltammetry were employed in this work. Several important thermodynamic parameters of the redox reactions of HBQCA were evaluated. Various physical parameters like apparent energy of activation, heterogeneous electron transfer rate constant and diffusion coefficient were also determined. On the basis of electrochemical results the pH dependent redox mechanism of HBQCA was proposed. Computational chemistry was used as a tool for the identification of oxidizable and reducible electropores and evaluation of some useful quantum chemical parameters for further characterization of the compound.

Two new ceramides have been isolated from Tanacetum artemisioides, besides the known constituents β -sitosterol and β -sitosterol glycoside. The structure elucidation of the isolated new compounds was based primarily on 1D and 2D NMR analysis, including COSY, HMQC, HMBC correlations. The compound 1 and 2 showed inhibitory activity against acetylcholinesterase

A reinvestigation with a modified extraction procedure of Tanacetum artemisioides resulted in the isolation and structure elucidation of one new ceramide named tanacetamide C and assigned structure 2R,3'R,3R,4'S,6R,4E-N-[3',4'-dihydroxydodecanoyl]-2-amino-4-nonacosene-1,3,6-triol (1). In addition 5,4'-dihydroxy-3,6,7-trimethoxyflavone (2), 5-hydroxy-3,6,7,4'-tetramethoxy flavone (3), leukodin (4) were also isolated for the first time from this species. The structure elucidation of the isolated new compound was based primarily on 1D and 2D NMR analysis, including COSY, HMQC, HMBC correlations.