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[reaction: see text] Biaryl bromides such as 1 (R=NO(2), H, OMe) undergo the Heck reaction to give both the expected products 3 ("retention") as well as "crossover" products 4 derived from a migration of Pd and net transfer of reactivity from one aryl ring to the other. Under the conditions used, crossover is increasingly favored when electron-deficient arenes are involved. Crossover products derived from transfer onto the pyridine ring have also been observed.

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The synthesis of azalamellarins, a new series of lactam analogues of biologically active lamellarins, was achieved using Cu(I)-mediated and microwave-assisted C-N(amide) bond formation. Seventeen azalamellarins, including N-allylazalamellarins and N-propylazalamellarins chi-D, L-N, and J-dehydro J, were synthesized and evaluated for their cytotoxicity against the cancer cell lines HuCCA-1, A-549, HepG2, and MOLT-3. The results showed that certain azalamellarins exhibited good activities in the micromolar IC(50) value range (IC(50)=the drug concentration that causes 50 % of cell-growth inhibition after 72 h of continuous exposure to the test molecule), comparable to their parent lamellarin analogue.

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Two new Lycopodium alkaloids, squarrosine A (1) and pyrrolhuperzine A (2), were isolated from the Thai and Philippine plant Huperzia squarrosa. (R)-2-Piperidineacetic acid (5) was a known alkaloid, but has now been isolated for the first time from a natural source. Their structures were elucidated using extensive spectroscopic analyses and, for pyrrolhuperzine A (2), confirmation by chemical transformation. The new compounds exhibited moderate acetylcholinesterase inhibitory activities.

a b s t r a c tSubtulene A, a new cyclic lipopeptide, was isolated from the culture broth of Bacillus subtilis SSE4. This antibiotic compound contained the seven common, L-Ser-7 and the unique b-amino acid-8 present in the iturin family. 1D and 2D NMR, as well as MS analyses, identified the b-amino acid as 3-amino-13-methyltetradec-8-enoic acid, an Iso C15 long chain b-amino acid. B. subtilis SSE4 was also found to produce iturin A. B. subtilis SSE4 culture filtrate exhibited both antifungal and antibacterial activities.

Croton hutchinsonianus HOSSEUS belongs to the family Euphorbiaceae. It is a shrub or small tree reaching 4-5 meters high and native to Thailand,1) where it is commonly called "Plao phae". In this paper, we describe the isolation and structure elucidation of newly isolated 3Ј-(4Љ-hydroxy-3Љ,5Љ-dimethoxyphenyl)-propyl benzoate, 3Ј-(4Љ-hydroxyphenyl)-propyl benzoate and four known compounds [3Ј-(4Љ-hydroxy-3Љ-methoxyphenyl)-propyl benzoate, poilaneic acid, farnesyl acetone and 4-hydroxybenzaldehyde] from the branches of this plant. The complete NMR assignment of 3Ј-(4Љ-hydroxy-3Љ-methoxyphenyl)-propyl benzoate was established for the first time in this paper. The inhibitory activities against the enzymes COX-1 and COX-2 and antifungal activities against Candida albicans were also performed on some of the isolated products. Results and DiscussionCompounds 1-6 were obtained from the ethyl acetate extract of C. hutchinsonianus after purification by Cosmosil C 18 -OPN, Sephadex LH 20 and silica gel column chromatography.HR-FAB-MS of 1 suggested a molecular formula of C 18 H 20 O 5 corresponding to nine degrees of unsaturation present in the molecule. The IR spectrum demonstrated the presence of a hydroxyl group (3446 cm Ϫ1) and a carbonyl group (1708 cm Ϫ1 ). The 1 H-NMR spectral data (Table 1) showed the presence of two benzene rings which was readily confirmed by analysis of the 1 H-1 H COSY, HMQC and HMBC spectral data. The 1 H-NMR spectral data showed three methylene groups (H-1Ј, H-2Ј, H-3Ј) bridging between benzoate and aromatic rings, two methoxyls at d 3.86 (each 3H, s) and one D 2 O-exchageable hydroxyl proton at d 5.40 appearing as a broad singlet suggestive of the phenylpropyl benzoate moiety with the substituents of hydroxyl and methoxyl groups on the aromatic ring. In addition, HMBC data for 1 conclusively demonstrated the correlations of methylene protons H-1Ј to C-1 and H-2Ј to C-1Љ and H-3Ј to C-2Љ and C-1Ј respectively. The 13 C-NMR spectrum showed the signal of carbonyl ester at d 166.6. The positions of two methoxyl groups and one hydroxyl group were established employing the HMBC technique (correlations as shown in Fig. 1). All data are consistent with the structure of 3Ј-(4Љ-hydroxy-3Љ,5Љ-dimethoxyphenyl)-propyl benzoate.Compound 2 has already been isolated from the flower of Gardenia taitensis DC, 2) however no NMR spectral data has been reported. The 1 H-and 13 C-NMR data of 2 are shown in Table 1.Compound 3 had a molecular formula of C 16 H 16 O 3 based on HR-FAB-MS. The 1 H-and 13 C-NMR data of 3 (Table 1) was similar to those of 1 except for the absence of two methoxyl groups at C-5Љ and C-3Љ. The 1 H-NMR spectral data of 3 showed the presence of the para-substituted benzene ring at d 7.08 (2H, d, Jϭ8.4 Hz, H-2Љ, H-6Љ); d 6.77 (2H, d, Jϭ8.4 Hz, H-3Љ, H-5Љ). The 2D NMR experiment on 3 also produced very similar results, indicating that both 1 and 3 were closely related.Compounds 1-3 were tested for antifungal activity against Candida albicans. They showed moderate activity * To whom corresponde...