Targets, elusive

Figure 8. Some hitherto elusive modules for two-and three-dimensional all-carbon scaffolding challenges for future targeted synthesis.

Numerous semiempirical studies have been made of semibullvalene and a wide range of derivatives (see Williams and Kurtz, 1988 Dewar and Jie, 1988, and references cited therein). Agreement with experimental data, where available, is excellent. Several target molecules are predicted to exhibit the elusive goal of neutral homoaromaticity which provides an enticing challenge for synthetic efforts. 

Marincola, F. M., Wang, E., Herlyn, M., Seliger, B., and Ferrone, S., 2003, Tumors as elusive targets of T-cell-based active immunotherapy, Trends Immunol 24 335-342. 

Since the advent of the stoichiometric Zr-promoted enyne bicyclization-carbonylation [19,20], development of its catalytic and enantioselecti ve version has been an attractive but elusive target. Although its catalytic but racemic version has recently been developed in the form of Zr-cataly zed cyclic carboalumination [39], there does not appear to be any successful report on Zr-catalyzed enantioselective enyne bicyclization-carbonylation, the closest process being that discussed in... 

Wittke S, Kaiser T, Mischak H. Differential polypeptide display The search for the elusive target. J Chromatogr B 2004 803(1) 17-26. 

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