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A new approach for the synthesis of N‐indolyl ketones and aldehydes was developed. In the reaction of N‐indolyl carboxylic acids with alkyl lithium, an interesting phenomenon appeared when using THF as solvent instead of ethyl ether.

A concise and efficient synthesis of (R)‐ and (S)‐2‐methylpiperazine in only five steps from (D)‐ and (L)‐alanine is described. The key step is reaction of benzylamine with a bifunctional molecule to build a six‐membered ring.

A new dibenzocyclooctadiene lignan named angustifolin D (1) together with four known lignans: kadsulignan L (2), kadsulignan N (3), schisantherin P (4) and meso-dihydroguaiaretic acid (5) were isolated from the stems of Kadsura angustifolia. Their structures and stereochemistries were elucidated by spectral studies. Compounds 2 and 5 showed moderate platelet-activating factor (PAF) antagonistic activities with IC50 values of 2.6 x 10(-5) and 4.1 x 10(-5) M, respectively.

Three new dibenzocyclooctadiene lignans, named angustifolin A, B and C, were isolated from the stems of Kadsura angustifolia. Their structures and stereochemistries were elucidated by spectral studies. (C) 1998 Elsevier Science Ltd. All rights reserved.

Two new 18(13--12)-abeo-lanostane triterpenoid acids, ananosic acids B (1) and C (2), were isolated from the stems of Kadsura anaosma. Their structures were elucidated by spectral studies and chemical transformation. Compounds 1 and 2 were evaluated for cytotoxicity using CCRF-CEM leukemia cells and HeLa cells.

New peracetylated 3,3′-(D-glycopyranosylidene)bis(1-propene), prepared from peracetylated anomeric sugar dihalides and allyltributyltin in excess under UV irradiation conditions (AIBN, ca. 35 °C), lent themselves to ring-closing olefin metathesis in the presence of Grubbs’ catalyst (6 mol %) to afford the corresponding peracetylated spiro[1,5-anhydro-D-glycopyranositol-1,4′-cyclopent-1′-enes] (D-gluco: 81%, D-manno: 89%, D-galacto: 72% isolated yield), which could be deacetylated quantitatively. The bis(allylation) reaction (D-gluco: 40%, D-manno: 34%, D-galacto: 24% isolated yield) was in competition with radical-induced rearrangement and elimination reactions. The last process, found to be favored at higher temperature (80 °C), opens an easy route to sugar dienes difficult to prepare otherwise.

A new approach for the synthesis of N‐indolyl ketones and aldehydes was developed. In the reaction of N‐indolyl carboxylic acids with alkyl lithium, an interesting phenomenon appeared when using THF as solvent instead of ethyl ether.

The 18-(13-->12 beta)-abeo-lanostene triterpenoid acid, ananosic acid A (1), and the dibenzocyclooctadiene lignan, ananosin A (2), were isolated from the stem bark of Kadsura ananosma. Their structures were elucidated by extensive spectral studies and the structure of 1 was confirmed by single crystal X-ray diffraction analysis.

Three triterpenoid acids, nigranoic acid (1), manwuweizic acid (2), schisandronic acid (3), and other four compounds were isolated from the stems of Schisandra propinqua. Compounds 1 and 2 showed significant cytotoxic effect against human decidual cells and rat luteal cells in vitro.

New peracetylated 3,3′-(D-glycopyranosylidene)bis(1-propene), prepared from peracetylated anomeric sugar dihalides and allyltributyltin in excess under UV irradiation conditions (AIBN, ca. 35 °C), lent themselves to ring-closing olefin metathesis in the presence of Grubbs’ catalyst (6 mol %) to afford the corresponding peracetylated spiro[1,5-anhydro-D-glycopyranositol-1,4′-cyclopent-1′-enes] (D-gluco: 81%, D-manno: 89%, D-galacto: 72% isolated yield), which could be deacetylated quantitatively. The bis(allylation) reaction (D-gluco: 40%, D-manno: 34%, D-galacto: 24% isolated yield) was in competition with radical-induced rearrangement and elimination reactions. The last process, found to be favored at higher temperature (80 °C), opens an easy route to sugar dienes difficult to prepare otherwise.

The acid dissociation constants of N-carboxymethyl-N-(p-hydroxy phenyl carbamoyl-methyl)-2,3-dihydroxy-5-carbomethoxy benzylamine (CHDCB) and the stability constants of its 1:1 complexes with alkaline earth, Cd(II), Co(II), Ni(II), Cu(II), Zn(II), Fe(III), Th(IV) and U(VI) ions have been determined at 25.0 ± 0.1 °C and at an ionic strength of 0.1 (KNO3) by pH titration method. The probable coordination sites have also been discussed.

PTD4-apoptin protein enters cells and harbors tumor-selective cell death activity. Dacarbazine is the mainstay of treatment for malignant melanoma. In this study, we investigated the cytotoxic effect of PTD4-apoptin protein and/or dacarbazine in mouse B16-F1 and human A875 and SK-MEL-5 melanoma cells in vitro and by means of a mouse B16-F1 melanoma model in vivo. PTD4-apoptin protein inhibits the growth of B16-F1, A875 and SK-MEL-5 melanoma cells in a dose-dependent manner, but not in normal human cell lines WI-38 and L-02. PTD4-apoptin combined with dacarbazine revealed a synergistic cytotoxic effect (coefficient of drug interaction