@article {3278,
	title = {TEMPLATION EFFECTS ON FORMATION OF A HEMICARCEPLEX},
	journal = {Supramolecular Chemistry},
	volume = {5},
	number = {1},
	year = {1995},
	note = {ISI Document Delivery No.: RX096Times Cited: 15Cited Reference Count: 36},
	pages = {31-37},
	type = {Article},
	abstract = {We have shown previously that the reaction to form carceplex 3 . guest has dramatic templation requirements where the best template molecule studied is one million times more effective at bridging the two bowl-shaped precursors than the poorest template. Here, we investigate the template requirements for the formation of hemicarceplex 4 . guest which is similar to carceplex 3 . guest in cavity size and shape. The two compounds differ in that 4 . guest lacks one of the four inter-bowl methylene bridges and thus has a portal and reduced symmetry relative to carceplex 3 . guest (C-2v vs D-4h). Thus, the template requirements for hemicarceplex 4 . guest are more stringent because the two howls can, in principle, misalign. We have found that despite these differences, the same template effect holds. We conclude that the same forces are at play in each reaction. These forces include 1) favorable van der Waals interactions between the template molecule and the forming cavity of the carceplex or hemicarceplex 2) unfavorable steric strain being imparted to the complex and 3) hydrogen bonds between the bowls. We also demonstrate the utility of matrix-assisted laser desorption ionization (MALDI) as a mild mass spectrometric technique for non-volatile organic compounds and complexes.},
	keywords = {4 PORTALS, BINDING, CAPTURE, CARCERANDS, CONSTRICTIVE, HOST-GUEST COMPLEXATION, LASER DESORPTION IONIZATION, MASS-SPECTROMETRY, POLYMERS, RECOGNITION, RELEASE},
	isbn = {1061-0278},
	url = {<Go to ISI>://A1995RX09600007},
	author = {Chopra, N. and Sherman, J. C.}
}
@article {6841,
	title = {LASER DESORPTION IONIZATION FOURIER-TRANSFORM ION-CYCLOTRON RESONANCE MASS-SPECTROMETRY OF CARBOHYDRATES .1. BACTERIAL OLIGOSACCHARIDES CONTAINING NEURAMINIC ACID OR PYRUVIC-ACID ACETAL GROUPS},
	journal = {Analytica Chimica Acta},
	volume = {241},
	number = {2},
	year = {1990},
	note = {ISI Document Delivery No.: EU533Times Cited: 14Cited Reference Count: 342ND INTERNATIONAL SYMP ON APPLIED MASS SPECTROMETRY IN THE HEALTH SCIENCESAPR 17-20, 1990BARCELONA, SPAINASTRA, APPL BIOSYST, BOEHRINGER MANNHEIM, COMISSIO INTERDEPT RECERCA \& INNOVAC TECHNOL, CONSEJO SUPER INVESTIGAC CIEN, CONSELLERIA ENSENYAMENT GENERALITAT CATALUNYA, FINNIGAN MAT, FONDO INVESTIGAC SANITARIA, REAL SOC ESPANOLA QUIMICA, GRP CROMATOG \& TECN AFINES, HEWLETT PACKARD},
	month = {Dec},
	pages = {187-199},
	type = {Proceedings Paper},
	abstract = {The positive- and negative-ion laser desorption ionization Fourier transform ion cyclotron resonance mass spectra of two known, underivatized, linear oligosaccharides obtained by enzymatic hydrolysis with bacterial viruses of the corresponding native bacterial capsular polysaccharides were analyzed. The high-resolution spectra, estimated to be from less than 1 nmol of sample, showed prominent pseudo-molecular ions, as well as fragment ions derived from glycosidic bond and ring cleavages. For some of these frequently observed ring fragments, structures are proposed by analogy to known even-electron gas phase fragmentations and even-electron solution chemistry. The structures of the capsular biopolymers were delineated from these fragmentations, confirming that Klebsiella pneumoniae serotype K3 capsular polysaccharide is made up of a pentasaccharide repeating unit, consisting of four hexoses, one hexuronic acid and one pyruvic acid acetal; and confirming that the tetrasaccharide repeating unit of Escherichia coli serotype K9 is composed of two hexoses, one acetamido hexose and one N-acetyl neuraminic acid. The analysis of oligosaccharides containing N-acetylated sugars was complicated by the fact that an amino hexose attached to a -C2H3O2 ring fragment shares the same elemental formula as an acetamido hexose. Nevertheless, other less ambiguous structural ions could be used for sequencing. Furthermore, analysis of the ring fragments also provided some indication of the positions of linkage of certain monosaccharide residues.},
	keywords = {BACTERIOPHAGE-BORNE ENZYMES, CAPSULAR, FAB, FAST ATOM BOMBARDMENT, GLYCOSIDES, ION CYCLOTRON RESONANCE, LASER DESORPTION IONIZATION, MS, OLIGOSACCHARIDES, POLYSACCHARIDE, SEQUENCE, SPECTRA},
	isbn = {0003-2670},
	url = {<Go to ISI>://A1990EU53300004},
	author = {Lam, Z. and Comisarow, M. B. and Dutton, G. G. S. and Parolis, H. and Parolis, L. A. S. and Bjarnason, A. and Weil, D. A.}
}
