Yuri Biba is a Staff Aero Performance Engineer with Dresser-Rand Company, in Olean, New York. He has been with the company since 1992, involved in turbocompressor selections, revamps and testing, focusing on aerodynamic design, analysis, performance prediction, and optimization of centrifugal compressor components. Dr. Biba received his M.Sc. degree in Aeronautical Engineering (with Honors, 198...

A new triterpene glycoside, 3-O-[(α-L-rhamnopyranosyl)(1→2)]-[β-D-glucuronopyranosyl-6-O-methyl ester]-olean-12-ene-28-olic acid (1) and a new indole alkaloid, 5-methoxy-2-oxoindolin-3-acetic acid methyl ester (5) were isolated from the leaves of Acanthopanax senticosus Harms along with six known compounds. The structures of the new compounds were determined by means of 2D-NMR experiments and c...

Two new friedelane-type triterpenes named 12alpha-hydroxyfriedelane-3,15-dione and 3beta-hydroxyfriedelan-25-al, together with six known compounds were isolated from the stems of Drypetes paxii Hutch. (Euphorbiaceae). Their structures were established on the basis of conventional 1 dimensional (1D) NMR methods, 2D shift-correlated NMR experiments and mass spectra. The five friedelane-type trite...

Glycyrrhizin, a pentacyclic triterpene glycoside, is the major phytochemical in licorice. This compound and its hydrolysis product glycyrrhetinic acid have been associated with the multiple therapeutic properties of licorice extracts. We have investigated the effects of 2-cyano substituted analogues of glycyrrhetinic acid on their cytotoxicities and activity as selective peroxisome proliferator...

Triterpenoids are used for medicinal purposes in many countries. Some, such as oleanolic and glycyrrhetinic acids, are known to be anti-inflammatory and anticarcinogenic. However, the biological activities of these naturally occurring molecules against their particular targets are weak, so the synthesis of new synthetic analogues with enhanced potency is needed. By combining modifications to bo...

A new complex triterpenoid saponin, polystachyasaponin, was isolated from leaves of Entada polystachya (L.) DC. (Leguminosae) by using chromatographic methods. Its structure was established as 15,16-dihydroxy-3-[[O-β -D-xylopyranosyl-(1→2)-O-α-L-arabinopyranosyl-(1→6)-2(acetylamino)-2-deoxy-β -D-glucopyranosyl]oxy]-(3β ,15α ,16α)-olean-12-en-28-oic acid O-D-apioβ -D-furanosyl-(1→3)-O-β -D-xylop...

One new and three known triterpenoid saponins were isolated and identified from Camellia oleifera seeds through IR, NMR, HR-ESI-MS and GC-MS spectroscopic methods, namely oleiferasaponin A₃, oleiferasaponin A₁, camelliasaponin B₁, and camelliasaponin B₂. The structure of oleiferasaponin A₃ was elucidated as 16α-hydroxy-21β-O-angeloyl-22α-O-cinnamoyl-23α-aldehyde-28-dihydroxymethylene-olean-12-e...

Vinca major L. is an evergreen perennial weed of family Apocynaceae, growing naturally in hilly areas Hazara region Khyber Pakhtunkhwa, Pakistan. Flowers this were collected from Khanspur, Ayubia during June 2021, shade dried and extracted pure methanol for two weeks. After filtration, the extract was analyzed by GC-MS identification possible bioactive compounds. ?-Amyrin compounds (32.49%) fol...