Methyl 3-dehydr-oxy-3-oxoursolate

Crystal structure and Hirshfeld surface analysis of 3-oxours-12-ene-27a,28-dioic acid (quafrinoic acid)

The title compound, C30H44O5, is a penta-cyclic triterpene isolated from the Cameroonian medicinal plant Nauclea Pobeguinii and known as quafrinoic acid. The mol-ecule is composed of five fused six-membered rings, four of which adopt a chair conformation and one a half-chair conformation. Intra-molecular C-H⋯O hydrogen-bond inter-actions exist, which generate S6 and S8 rings. In the crystal, mol-ecules are linked by pairs of O-H⋯O hydrogen bonds, linking R22(8) rings into chains running parallel to the a axis; these chains are further connected into layers parallel to the ab plane by C-H⋯O hydrogen bonds. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (79.4%) and O⋯H (20.4%) inter-actions.

Hyaluronidase Inhibitory Activity of Pentacylic Triterpenoids from Prismatomeris tetrandra (Roxb.) K. Schum: Isolation, Synthesis and QSAR Study

The mammalian hyaluronidase degrades hyaluronic acid by the cleavage of the β-1,4-glycosidic bond furnishing a tetrasaccharide molecule as the main product which is a highly angiogenic and potent inducer of inflammatory cytokines. Ursolic acid 1, isolated from Prismatomeris tetrandra, was identified as having the potential to develop inhibitors of hyaluronidase. A series of ursolic acid analogues were either synthesized via structure modification of ursolic acid 1 or commercially obtained. The evaluation of the inhibitory activity of these compounds on the hyaluronidase enzyme was conducted. Several structural, topological and quantum chemical descriptors for these compounds were calculated using semi empirical quantum chemical methods. A quantitative structure activity relationship study (QSAR) was performed to correlate these descriptors with the hyaluronidase inhibitory activity. The statistical characteristics provided by the best multi linear model (BML) (R² = 0.9717, R²cv = 0.9506) indicated satisfactory stability and predictive ability of the developed model. The in silico molecular docking study which was used to determine the binding interactions revealed that the ursolic acid analog 22 had a strong affinity towards human hyaluronidase.