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A new norcembranoidal diterpene, 1-epi-sinulanorcembranolide A (1), and a new cembranoidal diterpene, flexibilin D (2), were isolated from the soft corals, Sinularia gaweli and Sinularia flexibilis, respectively. The structures of new metabolites 1 and 2 were elucidated by spectroscopic methods, and compound 2 was found to significantly inhibit the accumulation of the pro-inflammatory iNOS and COX-2 proteins of the lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells. In addition, S. flexibilis yielded a known cembrane, 5-dehydrosinulariolide (3); the structure, including its absolute stereochemistry, was further confirmed by single-crystal X-ray diffraction analysis.

A convenient new method is developed for the preparation of 1‘,1‘‘‘-disubstituted biferrocenes which can be oxidized with iodine to a new series of mixed-valence compounds. The X-ray structures of 1‘,1‘‘‘-dimethoxymethyl, 1‘,1‘‘‘-diethoxyl, 1‘,1‘‘‘-dimethyl, 1‘,1‘‘‘-dihydroxymethyl, 1‘,1‘‘‘-dibenzoyloxymethyl, 1‘,1‘‘‘-dimethylthio, and 1‘,1‘‘‘-diethylthio neutral biferrocenes and the mixed-valence 1‘,1‘‘‘-diethoxyl, 1‘,1‘‘‘-dimethyl, 1‘,1‘‘‘-dibenzoyloxymethyl, and 1‘,1‘‘‘-diphenylthio biferrocenium triiodide salts have been determined at 298 K. The rates of intramolecular electron transfer in these mixed-valence cations were estimated by variable-temperature 57Fe Mossbauer experiment.

Adenocarcinomas in rats and humans frequently contain perivascular, degranulating mast cells that release heparin. Protamine is a low-molecular weight, cationic polypeptide that binds to heparin and neutralizes its anticoagulant properties. A novel magnetic resonance imaging (MRI) contrast agent containing protamine was synthesized. TTDASQ, the derivative of TTDA (3,6,10-tri(carboxymethyl)-3,6,10-triazadodecanedioic acid), was also synthesized and the kinetic stability of [Gd(TTDASQ)]- chelate containing phosphate buffer and ZnCl2 to measure the relaxation rate (R1) at 20 MHz was studied by transmetallation with Zn(II). The water-exchange rate (k(ex)298) of [Gd(TTDASQ)]- is 6.4 x 10(6) s(-1) at 25.0 +/- 0.1 degrees C which was obtained from the reduced 17O relaxation rates (1/T(1r) and 1/T(2r)) and chemical shift (omega(r)) of H(2)17O, and it is compared with that previously reported for the other gadolinium(III) complex, [Gd(DO3ASQ)]. The binding affinity assay showed that the (TTDASQ)3-pro19 has higher activity toward heparin. On the other hand, the effect of heparin on the relaxivity of the [Gd(TTDASQ)3-pro19] conjugate shows the binding strength (K(A)) is 7669 dm3 mol(-1) at pH 7.4 and the relaxivity (r(b)1) of the [Gd(TTDASQ)3-pro19]-heparin adduct is 30.9 dm3 mmol(-1) s(-1).