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.

Herein, the l-lactide polymerization rate of a series of Al complexes bearing ketimine ligands was investigated, and the polymerization characteristics between l-lactide and ε-caprolactone were compared.

Studies of the ring-opening polymerization of L-lactide (LA) using Na complexes with Schiff base ligands as catalysts have revealed high catalytic activity but poor controllability of the polymer molecular weight. In this study, Na complexes bearing ketiminate ligands instead of Schiff base ligands were synthesized and their application in LA polymerization was tested. The polymerization results revealed that the catalytic activity of Na complexes bearing ketiminate ligands was higher than that of Na complexes bearing Schiff base ligands, but the poor controllability of polymer molecular weight was still a drawback. However, the poor controllability could be improved by means of using a high concentration of initiators in the polymerization system at 0 °C for 1 min. L^Py–Na revealed the excellent controllability of polymer molecular weight depending on the ratio of [LA]/[initiator] (the molar averages of the number from 4500 to 35 000) with narrow polydispersity indexes, ranging from 1.29 to 1.35.

Three new cembrane-type diterpenoids, flexibilins A–C (1–3), along with a known cembrane, (−)-sandensolide (4), were isolated from the soft coral, Sinularia flexibilis. The structures of cembranes 1–4 were elucidated by spectroscopic methods. The structure of 4, including its absolute stereochemistry, was further confirmed by single-crystal X-ray diffraction analysis. Cembrane 2 displayed a moderate inhibitory effect on the release of elastase by human neutrophils.

Using a bioactivity-guided fractionation method, two coumarins: minumicrolineacetonide (1) and epimurpaniculol senecioate (2), were isolated from the leaves ofMurraya omphalocarpa Hayata (Rutaceae). Compound 1 had been previously synthesizedand was now isolated from natural sources for the first time, and compound 2, possessing anegative optical rotation value, is new. The structures and their stereochemistry were fullyelucidated on the basis of spectroscopic and X-ray crystallographic techniques. Bothcompounds 1 and 2 are active in the antiplatelet aggregation assay. Interestingly, thepossible acetonide artifact 1 displayed significant antiplatelet aggregation induced not onlyby AA and collagen but also by platelet activating factor (PAF).