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Peripheral myopization with multifocal contact lenses dominant design in myopic...

Peripheral myopization using a dominant design multifocal contact lens

Purpose: The purpose of this study was to characterize the central and peripheral refraction across the horizontal meridian of the visual fi eld without and with a multifocal dominant design soft contact lens of different add powers (+1.00 D to +4.00 D) in emmetropic eyes. Methods: Twenty right eyes from 20 emmetropic patients (mean spherical equivalent central refraction —0.06 ± 0.54 D) with a mean age of 21.6...

Synthesis and kinetic investigation of the selective acydolysis of para-substit...

Several derivatives of N-phenylacetyl-N-benzyl-alpha,alpha-dimethylglycine cyclohexylamide and their alpha,alpha-dibenzylglycine analogues were synthesised by a Ugi-Passerini reaction. In addition, a few analogues of the former but having an N-phenyl instead of a benzyl group at the nitrogen atom were synthesised. The compounds in each of these three sets differed from each other at the position 4 of the N-benz...

Kinetic investigation of the effect of the amino acid side chains in the select...

Accurate kinetic measurements of the rate constants for the acidolysis of five N-acetyl-N-(4-methoxybenzyl)-alfa,alfa-trialkyl glycine cyclohexyl amides in TFA were performed at 25.00 ºC and the reactions monitored by HPLC. The results were in all cases consistent with a first order behaviour with respect to the substrate. No direct correlation was obtained with this data between rate constant values and struct...

Effect of the amino acid substituents on amide bond cleavage in N-acyl-alpha,al...

alpha,alpha-Dialkylglycines and their peptides have attracted considerable attention, as they show unique biological activities and very stable secondary structures. In previous work, we have reported that the amide bond at the C-terminus of a series of alpha,alpha-dialkylglycine derivatives such as Deg, Dpg, Dibg and Dbzg is labile to acid; cleavage was achieved by reaction with neat TFA, the products being ob...