15-Hydroxy angustilobine A (269)
O
O
O
N
N
O
H
H
16-Epivincamine (270)
N
N
O
O
O
H
16R,19E-Isositsirikine (271)
N
OH
O
O
H
N
20(R)-Tubotaiwine (272)
N
N
H
O
O
4,6-Secoangustilobinal A (273)
O
O
O
HN
N
O
H
Akuammicine (274)
N
N
H
O
O
Alstolobine A (275)
O
O
N
O
N
O
O
H
Alstolucine B (276); R = H
Alstolucine D (277); R = OH
O
N
N
H
O
O
(-)-Alstolucine C (278)
O
N
+
N
H
O
O
O
-
Alstolucine E (279); R = OH
(-)-Alstolucine F (280); R = H
O
N
N
H
R
O
O
Angustilobine B (281)
O
O
O
N
N H
N
4 -Demethyl-12methoxyalstogustine (282)
N
N
H
O
O
O
OH
Nor-6,7-Seco
angustilobine A (283)
O
O
O
HN
N H
Undulifoline (284)
N
O
O
O
N
H
Vincadifformine (285)
N
N
H
O
O
Vincamine (286)
N
N
O
O
HO
Vinervine (287)
N
N
H
HO
O
O
R
Fig. 14.51 Chemical structures of various alkaloids from A. spatulata (269–287)
512
A. T. Paul et al.