Spatial structure and conformational state of dilupinine esters of dibasic acids
Conclusions1. The conformational states of dilupinine esters of dibasic acids and their protonated forms, and also their dimethiodides, have been studied by PMR spectroscopy.2. It has been shown that the nature of the conformational transformations of the trans-quinolizidine system of lupinine and of the dilupinine esters of dicarboxylic acids depends fundamentally on the acidity of the medium, the activity of water, the strength of intramolecular bonds, and the concentration of bases.
ACIDITY FUNCTIONS OF AQUEOUS SOLUTIONS OF STRONG ACIDS
CONTENTS I. Acidity scale for aqueous solutions of strong acids 803 II. Indicators for measuring acidity functions 805 III. Values of H0 for aqueous solutions of strong acids and oleum 807 IV. Accuracy of measurements of H0 812 V. Physical significance of the concept of "acidity of the medium" 813 VI. Relation between the acidity of the medium and the thermodynamic activity of water 814
Interaction of Diclofop-Methyl and MCPA on Wild Oats (Avena fatua)
Diclofop-methyl {methyl 2-[4-(2,4-dichlorophenoxy)phenoxy] propanoate} loses part of its activity on wild oats (Avena fatua L.) when it is applied in combination with ester or amine formulations of MCPA {[4-chloro-o-tolyl)oxy] acetic acid.} Uptake of diclofop-methyl is reduced in the presence of commercial formulations of MCPA, particularly amine formulations, which are only partly compatible with the diclofop-methyl formulation. With added MCPA, regardless of formulation, hydrolysis of diclofop-methyl to the acid diclofop is slowed down, both in intact wild oat plants and in a crude leaf extract. At the same time, conversion of any acid formed to inactive conjugates is accelerated in the presence of MCPA. It is concluded that the loss of activity of diclofop-methyl by MCPA can be accounted for by the effects of MCPA on uptake and metabolic conversion of diclofop-methyl.