A new mesembrine-type alkaloid, named sarniensine, was isolated together with tazettine, lycorine, the main alkaloid, and 3-epimacronine from Nerine sarniensis, with the last two produced for the first time by this plant. This Amaryllidaceae, which is indigenous of South Africa, was investigated for its alkaloid content, because the organic extract of its bulbs showed strong larvicidal activity with an LC value of 0.008μgμL against first instar Aedes aegypti larvae and with an LD value 4.6μg/mosquito against adult female Ae. aegypti, which is the major vector for dengue, yellow fever and the Zika virus. The extract did not show repellency at MED value of 0.375mgcm against adult Ae. aegypti. Sarniensine was characterized using spectroscopic and chiroptical methods as (3aR,4Z,6S,7aS)-6-methoxy-3a-(2'-methoxymethyl-benzo [1,3]dioxol-1'-yl)-1-methyl-2,3,3a,6,7,7a-hexahydro-1H-indole. It was less effective against larva at the lowest concentration of 0.1μgμL, however it showed strong adulticidal activity with an LD value of 1.38±0.056μgmosquito.

The synthesis of allocolchicine analogues is of importance as these compounds have been found to possess promising anticancer activity by affecting tubulin polymerization. In this paper, the synthesis of 28 novel substituted 6‐oxa‐allocolchicinoids is reported. The key steps involved in the synthesis were a Suzuki–Miyaura coupling reaction, followed by an acid‐catalyzed intramolecular transacetalization to afford the desired 5‐alkoxy‐5,7‐dihydrodibenzo[c,e]oxepines. In addition, when thiophenol and phenol were used in the transacetalization step, the 5‐(phenylsulfanyl)‐5,7‐dihydrodibenzo[c,e]oxepine and 4‐(5,7‐dihydrodibenzo[c,e]oxepin‐5‐yl)phenol skeletons were obtained, respectively. The cytotoxicity of the synthetic compounds was unfortunately not impressive; however, one of the compounds was shown to sensitize vincristine‐resistant leukemia and lymphoma cells to vincristine, a result vindicating further synthetic studies.

Scheme1.Preparation of N3-and N9-substituteda nalogues of 1.Scheme2.Preparation of N3-and N9-substituteda nalogues of 2.

Due to their involvement in almost all stages of cellular life, kinase biomolecular catalysts have been linked to cancer development and, thus, remain attractive drug targets for cancer therapeutics. 6-(3ꞌ-Hydroxypropyl)-, 6-(2ꞌ-hydroxyethyl)-, 6-(2ꞌ-propynyl)-and 6-(3ꞌ-propanenitrile)-pyrrolo[3,4-c]carbazole-1,3(2H,6H)-diones were synthesized as potential small molecule EGFR kinase inhibitors. The pyrrolocarbazole compounds were synthesized by way of a Diels-Alder approach involving N-alkylated 2-vinyl-1H-indole and maleimide as starting materials followed by aromatization with MnO 2 .

Synthesis of Diverse 6-Oxa-allocolchicinoids by a Suzuki-Miyaura Coupling, Acid-Catalyzed Intramolecular Transacetalization Strategy. -(YADAV, D. B.; TALELI, L.; VAN DER WESTHUYZEN, A. E.; FERNANDES, M. A.; DRAGOUN, M.; PROKOP, A.; SCHMALZ, H.-G.; DE KONING, C. B.; VAN OTTERLO*, W. A. L.; Eur. J. Org. Chem. 2015, 23, 5167-5182, http://dx.doi.org/10.1002/ejoc.201500573 ; Mol. Sci. Inst., Sch. Chem., Univ. Witwatersrand, Johannesburg 2050, S. Afr.; Eng.) -H. Hoennerscheid 51-172