Related Experiment Video
Updated: Sep 20, 2026

A Whole Mount In Situ Hybridization Method for the Gastropod Mollusc Lymnaea stagnalis
Published on: March 15, 2016
Mycalosides B-I, eight new spermostatic steroid oligoglycosides from the sponge Mycale laxissima
Alexandr S Antonov1, Shamil Sh Afiyatullov, Anatoly I Kalinovsky
1Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Prospect 100 let Vladivostoku, 690022 Vladivostok, Russian Federation.
Abstract:
New steroidal oligoglycosides mycalosides B-I (2-9) have been isolated from the polar extract of the Caribbean sponge Mycale laxissima, and their structures have been elucidated by 1D and 2D NMR ((1)H, (13)C, DEPT, COSY-45, COSY-RCT, HSQC, HMBC, and NOESY spectra) and MALDI-TOF mass spectrometry. Mycalosides B (2) and C (3) were shown to be 27- and 28-nor derivatives of the previously known tetraoside mycaloside A (1). Mycaloside D (4) differs from 1 only in the presence of an additional acetyl group in the carbohydrate moiety. Mycaloside E (5) was structurally identified as a 28-nor-4-dehydroxy derivative of 1. Mycalosides F-H (6-8), differing from each other by the structures of their side chains and nonacetylated (7, 8) or acetylated (6) tetrasaccharide carbohydrate moieties, have new 5(6)-unsaturated 3 beta,4 beta,21-trihydroxy-15-keto-steroidal aglycons. Mycaloside I (9) is a tetraoside of a new 7,24(28)-diunsaturated 3beta,15 beta,29-trihydroxystigmastane aglycon. It was established that the total fraction of the mycalosides as well as mycalosides A (1) and G (7) inhibit the fertilization of eggs by sperm of the sea urchin Strongylocentrotus nudus preincubated with these compounds.
More Related Videos
19:26Measuring Intracellular Ca2+ Changes in Human Sperm using Four Techniques: Conventional Fluorometry, Stopped Flow Fluorometry, Flow Cytometry and Single Cell Imaging
Published on: May 24, 2013
15:19Effect of Male Accessory Gland Products on Egg Laying in Gastropod Molluscs
Published on: June 22, 2014
Related Concept Videos
Calmodulin-dependent Signaling
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
Bacterial Phylum Spirochaetes
Bacterial Phylum Planctomycetes
Bacterial Phylum Tenericutes
Antifungal Agents
Diversity of Protists IV