Syzysamalactone, an Unusual 11-Carbon δ-Lactone Derivative from the Fresh Ripe Fruits of Syzygium samarangense (Wax
Yan-Ping Liu1,2,3, Zhen Xie1, Ruo-Qing Guan1
1Key Laboratory of Tropical Medicinal Resource Chemistry of Ministry of Education, Hainan Normal University, Haikou 571158, People's Republic of China.
Abstract:
To study the chemical constituents from the ripe fresh fruits of Syzygium samarangense (wax apple) and their potential health effects, a phytochemical investigation was undertaken. A new δ-lactone derivative, syzysamalactone (1), along with a known biogenetically related δ-lactone derivative, 6-pentyl-α-pyrone (2), were isolated from the fresh ripe fruits of S. samarangense. Syzysamalactone (1) is an unusual 11-carbon δ-lactone derivative, and its chemical structure and absolute configuration were elucidated by spectroscopic data analysis. A plausible biogenetic pathway for 1 was also proposed. Furthermore, the potential neuroprotective effects of compounds 1 and 2 were assessed. As a result, compounds 1 and 2 displayed notable neuroprotective effects with EC50 values of 0.29 ± 0.03 and 1.28 ± 0.06 μM, respectively, using the SH-SY5Y human neuroblastoma cell line. This is the first report of δ-lactone derivatives showing significant neuroprotective activities.
Related Concept Videos
Loss of Carboxy Group as CO2: Decarboxylation of Malonic Acid Derivatives
Alkylation of β-Diester Enolates: Malonic Ester Synthesis
Carboxylic Acid Derivatives: Overview
Nomenclature of Carboxylic Acid Derivatives: Amides and Nitriles
The IUPAC and common names of amides are derived from the parent carboxylic acid, by replacing the suffix “oic acid” and “ic acid,” respectively, with “amide.” In the following example, the IUPAC name ethanamide is derived from ethanoic acid, and the common name, acetamide, is obtained from acetic acid.
Aryldiazonium Salts to Azo Dyes: Diazo Coupling
Preparation and Reactions of Sulfides


