Crystal structure and DFT calculations of 3,4-seco-lup-20(29)-en-3-oic acid isolated from Wrightia tinctoria: Stacking of supramolecular dimers in the crystal lattice

3,4-Seco-lup-20(29)-en-3-oic acid (1), a rare triterpene, was isolated from Wrightia tinctoria R.Br (Family: Apocyanaceae). It appeared promising to study the structural chemistry of this compound because of its unique bio activity. X-ray diffraction analysis demonstrated that this compound consists of three six membered rings and one five membered ring. The first six membered ring (A) is in the twist boat form while the remaining two six membered rings (B, C) are in the chair form. The crystal of this compound belongs - to the monoclinic crystal system and space group P21. Lattice constituents are as follows: a = 13.074(6) Å, b = 11.972(5) Å, c = 17.394(7) Å; α = 90.00°, β = 98.20(13)°, γ = 90.00°; V = 2695(2) Å3, d = 1.094 Mg/m3, Z = 4. The optimized geometry of the reported molecule has been calculated with the DFT/B3LYP theory using 6-31G(d,p) basis set.