W0156

Norditerpenoid Alkaloids of Aconitum chasmanthum Stapf ex Holmes: Absolute Structures. Masood Parvez & Waseem Gul, Department of Chemistry, The University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4 Canada

Aconitum chasmanthum Stapf ex Holmes is a small herbaceous shrub which grows wild in Azad Jammu and Kashmir. It contains a large number of norditerpenoid alkaloids. The pharmacological properties of these alkaloids include the control and induction of cardiac arrhythmia, effects on smooth and skeletal muscles, central nervous activity and analgesia. The crystal structures of 3(-bikhaconine dichloroethane solvate (1), 3(-bikhaconine acetone solvate (2), 14-o-benzoyl-8-ethoxy-bikhaconine (3), and cocrystallized 14-o-benzoyl-8-ethoxy- and 14-o-benzoyl-8-methoxy-bikhaconines (4).

(1): C₂₅H₄₁NO₈.C₂H₄Cl₂, FW = 582.54, orthorhombic, P2₁2₁2₁, a = 12.167(2), b = 13.807(3), c = 17.355(2) Å, V = 2915.5(7) ų, Z = 4, D_c = 1.327 Mg m^-3, ( (Mo K() = 1.5418 Å, (= 2.41 mm^-1, R = 0.0696 for 4789 observed data [I > 2( (I)] using F². Flack parameter = 0.00(3).

(2): C₂₅H₄₁NO₈.C₃H₆O, FW = 541.67, orthorhombic, P2₁2₁2₁, a = 11.832(1), b = 14.216(2), c = 16.649(3) Å, V = 2800.4(7) ų, Z = 4, D_c = 1.285 Mg m^-3, ( (Mo K() = 1.5418 Å, (= 0.779 mm^-1, R = 0.0571 for 4806 observed data [I > 2( (I)] using F². Flack parameter 0.2(2).

(3): C₃₄H₄₉NO₈, FW = 599.74, monoclinic, P2₁, a = 10.096(1), b = 11.868(1), c = 13.566(5) Å, ( = 92.93(2)°,V = 1623.3(6) ų, Z = 2, D_c = 1.227 Mg m^-3, ( (Mo K() = 1.5418 Å, (= 0.701 mm^-1, R = 0.0658 for 5709 observed data [I > 2( (I)] using F². Flack parameter = -0.2(2).

(4): 0.65(C₃₃H₄₇NO₈).0.35(C₃₄H₄₉NO₈) , FW = 590.63, monoclinic, P2₁, a = 9.938(4), b = 11.876(5), c = 13.611(5) Å, ( = 91.96(1)°, V = 1605(1) ų, Z = 2, D_c = 1.222 Mg m^-3, ( (Mo K() = 1.5418 Å, (= 0.702 mm^-1, R = 0.0621 for 5468 observed data [I > 2((I)] using F². Flack parameter 0.0(2).