[1] Oblique nonlinear interactions based on the Kadomtsev-Petviashvili equation (also known as the two-dimensional Korteweg-de Vries equation) are extended to internal solitary waves (ISWs) to explain why the amplitude does not decrease owing to the geometric spreading of the cylindrical wavefronts in the South China Sea (SCS). This resonance theory is used to explain a satellite image exhibiting special features, and it is proposed that wave arcs of different amplitude resonate, providing a mechanism for reinforcing a wave by boosting the amplitude. The present theory suggests the amplitude of the ISW that propagates across the SCS basin depends on the interaction of ISWs originating from different sources; hence, studying the generation of an ISW from a single source location cannot predict the ISW correctly.

A series of novel pyrrolo[2,1-c][1,4]benzodiazepine (PBD) hybrids linked with indole carboxylates is described. These compounds were prepared by linking C-8 of 3 (DC-81) with an indole 2-carbonyl moiety (9) through carbon chain linkers to afford PBD hybrid agents 17-21 in good yields. Preliminary in vivo tests show that these hybrid agents have potent antitumor activity. The cytotoxic studies of the hybrid agents on human melanoma A2058 cells indicate most of the hybrids induced higher cytotoxicity, better DNA-binding ability, an increase in the apoptotic sub-G1 population, and a significant reduction in deltapsi(mt) relative to compound 3. In addition, DNA flow cytometric analysis shows that hybrids actively induce a marked loss of cells from the G2/M phase of the cell cycle, which progresses to early apoptosis as detected by flow cytometry after double-staining with annexin V and propidium iodide (PI). Thus, we suggest that the hybrid agents are potent inducers of cell apoptosis in A2058 cells.

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Borane reduction of ether-protected aromatic lactams produces 1-alkyl-1,2,3,4-tetrahydroquinolines (5 and 6) in excellent yields. This reaction provides a novel one-pot tandem process for reduction of amide group and N-protected groups. Experimental results demonstrate that the reaction proceeds through two consecutive elimination and reductions via two C-O bond cleavages to form the foresaid products.

A New Synthesis of 3-Alkyl-1-isoindolinones. -Various title compounds are efficiently prepared via alkylation of phthalimide (I) followed by reduction with sodium cyanoborohydride in acidic medium. -(WANG*, E.-C.; CHEN, H.-F.; FENG, P.-K.; LIN, Y.-L.; HSU, M.-K.; Tetrahedron Lett. 43 (2002) 50, 9163-9165; Sch. Chem., Kaohsiung Med. Coll., Kaohsiung 807, Taiwan; Eng.) -Mais 07-095