Molecular umbrellas

Journal of the American Chemical Society

Volumn 118, Issue 6, 1996, Pages 1573-1574

  Janout, Vaclav ^a   Lanier, Marion ^a   Regen, Steven L ^a  

^a LEHIGH UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

SURFACTANT;

ARTICLE; DRUG DESIGN; FLUORESCENCE; STRUCTURE ACTIVITY RELATION;

EID: 0029892370     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja953261v     Document Type: Article

References (10)

1. (a) Stein, T. M.; Gellman, S. H. J. Am. Chem. Soc. 1992, 114, 3943.
2. (b) McQuade, D. T.; Barrett, D. G.; Desper, J. M.; Hayashi, R. K.; Gellman, S. H. J. Am. Chem. Soc. 1995, 117, 4862.
3. (a) Cheng, Y.; Ho, D. M.; Gottlieb, C. R.; Kahne, D.; Bruck, M. A. J. Am. Chem. Soc. 1992, 114, 7319.
4. (b) Venkatesan, P.; Cheng, Y.; Kahne, D. J. Am. Chem. Soc. 1994, 116, 6955.
5. Burrows, C. J.; Saute, R. A. J. Inclusion Phenom. 1987, 5, 117.
6. Hjelmeland, L. M.; Nebert, D. W.; Osborne, J. C. Anal. Biochem. 1983, 130, 72.
7. 1H NMR (360 MHz) and HRMS analyses.
8. The cmc of I, which was determined in pure water by UV methods (Shoji, N.; Ueno, M.; Meguro, K. J. Am. Oil Chem. 1978, 55, 297) was 2.5 μM. In addition, the fluorescence intensity of I in pure water was directly proportional to its concentration within the range of 0.5 and 5.0 μM; a discontinuity at the 5.0 μM concentration, however, was noted. This discontinuity is presumed to reflect the onset of aggregation. The fact that the "turning point" for I (i.e., the DME/water ratio at which a minimum fluorescence intensity is observed) occurs at exactly the same DME/water ratio (10/90 v/v) when 1.0 and 0.5 μM solutions of umbrella are employed also argues against the possibility that this turning point reflects a critical micelle concentration.
9. MacGregor, R. B.; Weber, G. Nature 1986, 319, 70.
10. In preliminary studies, we have found that a molecular umbrella can enhance the partitioning of a polar compound from water into an organic phase. Thus, spermidine, bearing a cholic acid group at each end. significantly enhances the partitioning of picric acid from water into chloroform. Although the structure of this umbrella/picric acid complex remains to be established, a likely possibility is one in which the umbrella adopts a shielded conformation that covers over picric acid and holds it in place through acid/base interaction with the secondary amine group of spermidine: Vigmond, S.; Janout, V.; Regen, S. L., unpublished results.