Complexation of benzhexol and β-cyclodextrin was studied in aqueous medium. The formation of inclusion complex and its stoichiometry were determined by NMR titration method. ROESY spec-trum, recorded with a mixing ti...Complexation of benzhexol and β-cyclodextrin was studied in aqueous medium. The formation of inclusion complex and its stoichiometry were determined by NMR titration method. ROESY spec-trum, recorded with a mixing time of 0.5 s in few minutes, displayed crosspeaks between phenyl ring of benzhexol and β-cyclodextrin cavity protons established the inclusion of phenyl ring into the cavity. No inference about the distances between interacting protons could be drawn due to spin diffusion. However, analysis of peak intensity ratios of intermolecular crosspeaks suggested partial penetration of phenyl ring from wider side. Molecular mechanics studies supported these conclusions and the lowest energy conformation was proposed as the probable structure of 1:1 benzhexol-β-cyclodextrin complex.展开更多
Since the discovery of hF-GRP, several analogs have been synthesized in order to see their effects on the gonadotropin releasing activity, either as agonists or antagonists to this peptide. TF14 is one of these analog...Since the discovery of hF-GRP, several analogs have been synthesized in order to see their effects on the gonadotropin releasing activity, either as agonists or antagonists to this peptide. TF14 is one of these analogs, whose 14th position in the primary sequence is Phe instead of Asn in hF-GRP, while its activity is doubled. 2D-NMR (TOCSY, ROESY) was used to determine the conformation of TF14 in solution. Compared with hF-GRP, the whole peptide is in a non-typical more extended conformation, which may give some due to the relation between structure and function of these two peptides.展开更多
The complexation of triprolidine hydrochloride （TRP） and β-cyclodextrin （β-CD） in deuterium oxide was investigated by 400 MHz 1^H NMR spectroscopy. The 800 MHz 2D ROESY data revealed that two 1 ：1 and one 2 ：...The complexation of triprolidine hydrochloride （TRP） and β-cyclodextrin （β-CD） in deuterium oxide was investigated by 400 MHz 1^H NMR spectroscopy. The 800 MHz 2D ROESY data revealed that two 1 ：1 and one 2 ： 1 β-CD-TRP inclusion complexes were formed. Both aromatic moieties （p-tolyl and pyridyl ring） has entered into the β-CD cavity, confirming the existence of two different equilibria for 1 ： 1 inclusion complexes in which p-tolyl ring of the guest is more tightly held by the host cavity. The ROE intermolecular interactions provided the plausible structures of these 1 ： 1 and 2 ： 1 stoichiometric inclusion complexes of β-CD-triprolidine hydrochloride in solu- tion.展开更多
文摘Complexation of benzhexol and β-cyclodextrin was studied in aqueous medium. The formation of inclusion complex and its stoichiometry were determined by NMR titration method. ROESY spec-trum, recorded with a mixing time of 0.5 s in few minutes, displayed crosspeaks between phenyl ring of benzhexol and β-cyclodextrin cavity protons established the inclusion of phenyl ring into the cavity. No inference about the distances between interacting protons could be drawn due to spin diffusion. However, analysis of peak intensity ratios of intermolecular crosspeaks suggested partial penetration of phenyl ring from wider side. Molecular mechanics studies supported these conclusions and the lowest energy conformation was proposed as the probable structure of 1:1 benzhexol-β-cyclodextrin complex.
基金Project supported by the National Natural Science Foundation of China.
文摘Since the discovery of hF-GRP, several analogs have been synthesized in order to see their effects on the gonadotropin releasing activity, either as agonists or antagonists to this peptide. TF14 is one of these analogs, whose 14th position in the primary sequence is Phe instead of Asn in hF-GRP, while its activity is doubled. 2D-NMR (TOCSY, ROESY) was used to determine the conformation of TF14 in solution. Compared with hF-GRP, the whole peptide is in a non-typical more extended conformation, which may give some due to the relation between structure and function of these two peptides.
文摘The complexation of triprolidine hydrochloride （TRP） and β-cyclodextrin （β-CD） in deuterium oxide was investigated by 400 MHz 1^H NMR spectroscopy. The 800 MHz 2D ROESY data revealed that two 1 ：1 and one 2 ： 1 β-CD-TRP inclusion complexes were formed. Both aromatic moieties （p-tolyl and pyridyl ring） has entered into the β-CD cavity, confirming the existence of two different equilibria for 1 ： 1 inclusion complexes in which p-tolyl ring of the guest is more tightly held by the host cavity. The ROE intermolecular interactions provided the plausible structures of these 1 ： 1 and 2 ： 1 stoichiometric inclusion complexes of β-CD-triprolidine hydrochloride in solu- tion.
