1H and 13C NMR of 3-O and 4-O conjugates of dopamine and other catecholamines.
Dopamine and its conjugates are widely distributed among biological species and are utilized for a variety of functions. Insects metabolize dopamine for cuticle melanization and sclerotization. Among the most abundant dopamines found in the larval and pupal development stages of Manduca sexta, the tobacco hornworm, are N-acetyldopamine and N-beta-alanyldopamine. In addition, glycosylated derivatives of these dopamines are found mainly in the hemolymph just prior to cuticulogenesis. The 1H and 13C NMR resonances of dopamine, its 3-O-methyl, 4-O-methyl, N-acetyl, and N-beta-alanyl derivatives, norepinephrine, 4-O-(beta-D-glucuronopyranosyl)dopamine, and the glycosylated products of N-beta-alanyldopamine and dopamine have largely been assigned. Assignments were based on one- and two-dimensional NMR analyses of the above compounds combined with that of specifically enriched [C7-13C]dopamine. 1H NMR showed that the major glycosylated natural product isolated from M. sexta pupal hemolymph was a 3-O-glycosyl derivative of N-beta-alanyldopamine. 13C NMR confirmed that the carbohydrate was D-glucose probably in a beta-linkage. 1H NMR of the aromatic ring protons provided the most definitive method to distinguish 3-O- from 4-O-derivatives of dopamine. In addition, the 3-O-glucosyl conjugate of N-beta-alanyldopamine had unique chemical shifts and coupling patterns compared to those of 4-O-(beta-D-glucuronosyl)- and 3-O-(beta-D-glucopyranosyl)dopamine.
Mueller
D D
DD
Department of Biochemistry, Kansas State University, Manhattan 66506.
Morgan
T D
TD
Wassenberg
J D
JD
Hopkins
T L
TL
Kramer
K J
KJ
D000818:Animals; D004298:Dopamine / Q000031:analogs & derivatives* / Q000737:chemistry*; D006031:Glycosylation; D007814:Larva / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D009036:Moths / Q000737:chemistry* / Q000254:growth & development; D011679:Pupa / Q000737:chemistry
C006374:N-acetyldopamine; C038990:N(beta)-alanyldopamine; D004298:Dopamine