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.
Three New C19-Diterpenoid Alkaloids from Delphinium Bonvalotii
Three new lycoctonine-type C19-diterpenoid alkaloids, bonvalotidine A, bonvalotidine B, and bonvalotidine C, along with sixteen known alkaloids, were isolated from the roots of Delphinium bonvalotii Franch. Their structures were established by spectral analysis and chemical methods.
Synthesis of 2,4-dideoxy-.beta.-D-erythro-hexopyranosyl nucleosides
The synthesis of 1-(2,4-dideoxy-β-D-erythro-hexopyranosyl)thymine (12) 1 was accomplished using two different synthetic routes. It was obtained starting either from 1,2:5,6-di-O-isopropylidene-α-D-glucofuranose or from tri-O-acetyl-D-glucal. The other modified nucleosides, with either a cytosine, guanine, or adenine moiety, were synthesized using the second reaction scheme. Deoxygenation reactions were accomplished with the (2,4-dichlorophenoxy)thiocarbonyl derivatives generated in situ