Alkaloids of Delphinium corumbosum
SummaryFromDelphinium corumbosum Rgl. have been isolated methyllycaconitine, a new base which has been called delcorine, and a base with mp 93–95°C. On the basis of its chemical and spectral characteristics, a lycoctonine skeleton has been established for delcorine with α-hydroxy groups at C1 and C10, a β-hydroxy group at C6, a methylenedioxy group at C7 and C8, a β-methoxy group at C15, and a methoxy group at C19.
THE PARTIAL STRUCTURES OF ACONITINE AND ACONITOLINE
In aconitoline (C33H41O10N), the product of the oxidation of aconitine with chromic acid, the presence of an αβ-unsaturated carbonyl group has been confirmed. The determination of the basic strengths of aconitoline and its various hydrolytic and reduction products revealed a very strong influence of the carbonyl on the basicity of the alkaloid. It was concluded that the secondary hydroxyl that becomes oxidized must be located in close proximity to the nitrogen. Partial structures are suggested to represent both aconitine and aconitoline.
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.