Murrastifoline-F: first total synthesis, atropo-enantiomer resolution, and stereoanalysis of an axially chiral N,C-coupled biaryl alkaloid.

The first total synthesis of the Murraya alkaloid murrastifoline-F (3), an unsymmetric, N,C-bonded heterobiarylic biscarbazole, is described. Starting from the likewise naturally occurring-but here synthetically prepared-"monomer" murrayafoline-A (6), lead tetraacetate-mediated oxidative non-phenolic biaryl coupling gives 3 as the main regioisomer. The existence of this natural product as a pair of stable atropo-enantiomers was demonstrated analytically through LC-CD investigations. Preparatively, the racemate resolution succeeded by O-demethylation, derivatization with Mosher's reagent, and chromatographic separation of the resulting diastereomers. The absolute configurations of the atropisomers were assigned by CD spectroscopy in combination with quantum chemical CD calculations at the stage of the alkaloid 3 and by ROESY experiments of the diastereomeric Mosher derivatives. In the root extract of the curry leaf plant Murraya koenigii (Rutaceae), murrastifoline-F (3) was found to exist as a 56:44 mixture in favor of the M-enantiomer, by LC-CD coupling.

Infiltration of lung carcinomas with macrophages of the 27E10-positive phenotype.

In order to gain insight into the role of macrophages in human lung carcinomas, we investigated material from 35 lung carcinomas and 5 healthy lungs with 4 different antibodies (CD68, MRP8, MRP14, 27E10) recognizing different macrophage subtypes. Infiltration with CD68-positive macrophages was highest and comparable in healthy lungs and lung carcinomas. Compared to healthy lungs, the infiltration of MRP8- and MRP14-positive macrophages was reduced in lung carcinomas while the number of 27E10-positive cells was enhanced. No difference in the infiltration of macrophages was observed between the different histological subtypes of carcinomas such as squamous carcinoma, small lung carcinoma, adenocarcinoma and bronchio-alveolar carcinoma. Furthermore, we present a highly suitable technique for the isolation and enrichment of macrophages from human lung carcinomas resulting in a 5-10 fold enrichment and a yield of e.g. 2-3 x 10(6) 27E10-positive macrophages/g tumor biopsy. Together with the recent findings that 27E10-positive macrophages are prevalent in early acute inflammation and release cytotoxic mediators and to inhibit tumor cell proliferation our findings suggest that 27E10-positive macrophages may play a role in antitumor cytotoxicity in human lung carcinomas.