Solid state and solution conformation of 6-{4-[N-tert-butoxycarbonyl-N- (N'-ethyl)propanamide]imidazolyl}-6-deoxycyclomaltoheptaose: Evidence of self-inclusion of the Boc group within the β-cyclodextrin cavity
Solid state and solution conformation of 6-{4-[N-tert-butoxycarbonyl-N- (N'-ethyl)propanamide]imidazolyl}-6-deoxycyclomaltoheptaose: Evidence of self-inclusion of the Boc group within the β-cyclodextrin cavity(462 views) Impellizzeri G, Pappalardo G, D'Alessandro F, Rizzarelli E, Saviano M, Iacovino R, Benedetti E, Pedone C
European J Org Chem (ISSN: 1434-193x), 2000; (6): 1065-1076.
Affiliations: Dipartimento di Scienze Chimiche, Università di Catania, V. Le A. Doria 6, I-95125 Catania, Italy
Ist. per lo Stud. delle Sostanze N., Alimentare e Chimico-Farmaceutico, Sezione Stud. Modelli Metallo E., V. Le A. Doria 6, I-95125 Catania, Italy
Biocrystallography Research Centre, C. N. R., Univ.̀ Federico II di Napoli, via Mezzocannone, 4, I-80134 Napoli, Italy
Istituto per lo Studio delle Sostanze Naturali di Interesse Alimentare e Chimico-Farmaceutico, Sezione per lo Studio di Modelli di Metallo Enzimi, C.N.R., V. Le A. Doria 6, I-95125 Catania, Italy
References: Not available.
Solid state and solution conformation of 6-{4-[N-tert-butoxycarbonyl-N- (N'-ethyl)propanamide]imidazolyl}-6-deoxycyclomaltoheptaose: Evidence of self-inclusion of the Boc group within the β-cyclodextrin cavity
A new modified β-cyclodextrin (β-CD) derivative 1 that was functionalized in position 6 with Boc-Carcinine was synthesised and its crystal structure was determined. The structure reveals a 'sleeping swan'- like shape, the covalently bonded Boc-Carcinine moiety forming a folded structure with the Boc group inserted within the hydrophobic cavity of the β-cyclodextrin. The conformation of the Carcinine moiety is determined by the inclusion of the Boc group and is further stabilised by three intramolecular hydrogen bonds, two between the amide N1-H group, the carbonyl C'1=O1 group and a primary hydroxylic group of the glucose unit 5, one between the carbonyl C'O=O0 group and the primary hydroxylic group of the glucose unit 2. The β-CD macrocycle differs only slightly from unmodified β-CDs, maintaining an approximate sevenfold symmetry. The solution structure of the new β-CD derivative was investigated by NMR spectroscopy and circular dichroism (c.d.) spectroscopy. In addition to a complete (1H and 13C) assignment of the pendant Boc-Carcinine group, the NMR study allowed the assignment of all the proton resonances associated with the β-CD macrocycle. Furthermore, NMR and c.d. results indicated that the self-inclusion of the Boc group within the β-CD cavity is retained in aqueous solution. In order to estimate the strength of this self-inclusion complex a series of competition experiments with the external guest 1-adamantanol was carried out using c.d. spectroscopy.
Solid state and solution conformation of 6-{4-[N-tert-butoxycarbonyl-N- (N'-ethyl)propanamide]imidazolyl}-6-deoxycyclomaltoheptaose: Evidence of self-inclusion of the Boc group within the β-cyclodextrin cavity
Solid state and solution conformation of 6-{4-[N-tert-butoxycarbonyl-N- (N'-ethyl)propanamide]imidazolyl}-6-deoxycyclomaltoheptaose: Evidence of self-inclusion of the Boc group within the β-cyclodextrin cavity
Kállay C, Dávid A, Timári S, Nagy EM, Sanna D, Garribba E, Micera G, De Bona P, Pappalardo G, Rizzarelli E, Sóvágó I * Copper(II) complexes of rat amylin fragments(569 views) Dalton T (ISSN: 1477-9234, 1477-9226, 1477-9234electronic), 2011 Oct 14; 40(38): 9711-9721. Impact Factor:3.838 ViewExport to BibTeXExport to EndNote