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The title compounds are prepared by three-component cyclocondensation of phtalhydrazide, benzaldehydes, and malononitrile or ethyl cyanoacetate under environmentally friendly conditions.

Two new naturally occurring alkaloids, nothapodytines A and B, were isolated and characterized from the stems of Nothapodytes foetida.

Series of 1,2-diarylpyrroles has been synthesized and found to contain very potent and selective inhibitors of the human cyclooxygenase-2 (COX-2) enzyme. The paper describes short and practical syntheses of the target molecules utilizing the Paal−Knorr reaction. Electrophilic substitution on 1 proceeds in a regioselective fashion, and the method was used to generate a number of tetrasubstituted pyrroles. Detailed SAR on the series has been studied by modifications of the aryl rings and the substituents in the pyrrole ring. Diarylpyrrole 1 is a very potent (COX-2, IC50 = 60 nm) and selective (COX-1/COX-2 = >1700) inhibitor whereas the isomeric 2 is completely inactive against COX-2. Modifications of the substituents on the fluorophenyl ring in 1 yields very potent inhibitors of COX-2 (IC50 = 40−80 nm) with excellent selectivity (1200 to >2500) vs COX-1. Analog 20 containing a sulfonamide group is an excellent inhibitor of COX-2 with an IC50 of 14 nm. Tetrasubstituted pyrroles containing groups such as COCF...

Series of 1,2-diarylimidazoles has been synthesized and found to contain highly potent and selective inhibitors of the human COX-2 enzyme. The paper describes a short synthesis of the target 1,2-diarylimidazoles starting with aryl nitriles. Different portions of the diarylimidazole (I) were modified to establish SAR. Systematic variations of the substituents in the aryl ring B have yielded very potent (IC50 = 10−100 nm) and selective (1000−12500) inhibitors of the COX-2 enzyme. The study on the influence of substituents in the imidazole ring established that a CF3 group at position 4 gives the optimum oral activity. A number of the diarylimidazoles showed excellent inhibition in the adjuvant induced arthritis model (e.g., ED50 = 0.02 mpk for 22 and 34). The diarylimidazoles are also potent inhibitors of carrageenan-induced edema (ED50 = 9−30 mpk) and hyperalgesia (ED50 = 11−40 mpk). Several orally active diarylimidazoles show no GI toxicity in the rat and mouse up to 200 mpk.

Eight new phenylalkynes, capillaridins A-H, together with three known compounds, capillin, capillene and O-methoxycapillene, were isolated and identified from the aerial parts of Artemisia capillaris.

Three new dehydroshogaols have been isolated from the rhizomes of Zingiber officinale. Their structures were established by spectroscopic analysis and synthesis.

Reinvestigation of the root of Rhinacanthus nasutus afforded, in addition to rhinacanthin-A to -D reported previously, two new dimethyldihydropyranonaphthoquinone esters (5, 6) and eight new 2-hydroxy-1,4-naphthoquinone esters (7-14) were isolated. The stereochemistry of rhinacanthin-A was determined as the R configuration. Compounds rhinacanthin-G to -N, belong to a class of 2-hydroxy-3-(3-hydroxy-2,2-dimethylpropyl)-1,4-naphthoquinone esters, and so far have been isolated only in this plant. Their biosynthesis is also discussed.

Three novel skeleton sesquiterpenes, namely, madolin-F (1), -G (2a), and -H (3), were isolated and characterised from the fresh roots and stems of Aristolochia heterophylla. Madolin-F belongs to a novel skeleton, normaaliane type. Madolin-G and -H were constructed from three- and eleven-membered rings and named madolin type.

Seven denitroaristolochic acids, incuding four new compounds, sodium aristofolin-A, aristofolin-B-D and three known compounds, aristofolin-A, aristolic acid and methyl aristolate were isolated from the leaves of Aristolochia cucurbitifolia. Their structures were determined by spectroscopic methods.

Two new phenanthrene derivatives, aristoliukine-A, -B, and a benzenoid, sodium (2R)-(p-hydroxyphenyl)-lactate, together with thirty-three known compounds were isolated from the fresh leaves of Aristolochia kaempferi. Structures were elucidated by spectral analysis. Among the new compounds, sodium (2R)-(p-hydroxyphenyl)lactate was determined to be in the salt form by IR and 1 H-NMR methods.

A denitro-aristolochic acid derivative, aristofolin-A, together with ten known compounds, were isolated from the fresh flowers of Aristolochia kaempferi. The structures of these compounds were determined by spectral analysis.

Continuing our investigation on the bioactive compounds from the plant of Aristolochia genus in Taiwan, we isolated one new aristolochic acid derivative, aristolochic acid-VII methyl ester; one new dihydrophenanthrenelactone, aristolide-C; four new benzenoids, 2'-hydroxyethyl 4-hydroxybenzoate, ariscucurbin-A, -B and -C, together with forty-six known compounds from the fresh Aristolochia cucurbitifolia.

Four new glycosides, namely mudanpiosides-G, -H, -I and mudanoside-A together with three known compounds, gallic acid, adenosine and p-hydroxybenzoic acid were isolated from the root bark of Paeonia suffruticosa. Their structures have been determined on the basis of spectral evidence.

Seven new compounds, sodium aristolochate-VII (1), aristolactam-CIV (2), madolin-I (3), -J (4), -K (5), -L (6) and -M (7) together with 71 known compounds were isolated and characterized from the fresh root and stem of Aristolochia heterophylla Hemsl. Their structures were determined by spectral methods. Compound 8 was revised as aromadendrane-4beta, 10beta-diol by spectral data and single-crystal X-ray analysis.

A new biscoumarin, namely citrumedin-A [6,6',7,7'-tetramethoxy-3,3'-biscoumarin] (1), together with twenty two known compounds were isolated from the stem bark of Citrus medica L. var. sarcodactylis Swingle. The structure of this new compound was completely elucidated using a combination of 2D NMR techniques (COSY, NOESY, HMQC and HMBC) and HR-EI-MS analyses. The known compounds were identified by comparison of their spectroscopic and physical data with those reported in the literatures. The isolates were also screened their cytotoxicity against Daoy, Hep2, MCF-7 and Hela cell lines. Lonchocarpol A (12) showed marginally cytotoxic activity against those four cancer cell lines.

Four new compounds, three phenanthrene derivatives, aristolochic acid-III methyl ester (1), cepharanone C (2), and sodium 7-hydroxyl-8-methoxyaristolate (3), and the benzoate derivative, sodium 3,4-dimethoxybenzoate (4), together with 53 known compounds were isolated and characterized from the fresh root and stem of Aristolochia cucurbitifolia. Their structures were elucidated by spectral analyses and chemical transformations. The cytotoxicity and antiplatelet activity of the isolated compounds are also discussed.