https://pubs.rsc.org/en/content/articlepdf/2019/NP/C8NP00092A

Marine natural products.

https://www.int-res.com/articles/meps/207/m207p225.pdf

Marine chemical ecology

Recent insights have revolutionized our understanding of the importance of chemical signals in influencing vertebrate behaviour. Previously unknown families of pheromonal signals have been identified that are expanding the traditional definition of a pheromone. Although previously regarded as functioning independently, the main olfactory and vomeronasal systems have been found to have considerable overlap in terms of the chemosignals they detect and the effects that they mediate. Studies using gene-targeted mice have revealed an unexpected diversity of chemosensory systems and their underlying cellular and molecular mechanisms. Future developments could show how the functions of the different chemosensory systems are integrated to regulate innate and learned behavioural and physiological responses to pheromones.

Pheromonal communication in vertebrates

Bile salts of vertebrates: structural variation and possible evolutionary significance.

Pessimism about the prospects of eradicating invasive species or managing them at acceptably low densities is fostered by publicity about failures, but it is often unwarranted. Many species, including insects, plants, and aquatic invaders of various taxa, have been eradicated, and a variety of management techniques have maintained others at low densities for long periods. Many of these projects entailed low-tech, scorched-earth approaches, often using mechanical, physical, or chemical means. Others required sophisticated scientific research. There are at best rough guidelines rather than general rules about what approach to undertake. It is therefore important in each case to consider the full range of possible methods for eradication or long-term control, including the possibility of marshalling a massive amount of physical labor.

We can eliminate invasions or live with them. Successful management projects

This protocol details the most commonly used nuclear magnetic resonance (NMR)-based method for deducing the configuration of otherwise unknown stereogenic, secondary carbinol (alcohol) centers (R1R2CHOH (or the analogous amines where OH is replaced by NH2)). This 'Mosher ester analysis' relies on the fact that the protons in diastereomeric alpha-methoxy-alpha-trifluoromethylphenylacetic acid (MTPA) esters (i.e., those derived from conjugation of the carbinol under interrogation with MTPA) display different arrays of chemical shifts (deltas) in their 1H NMR spectra. The protocol consists of the following: (i) preparation of each of the diastereomeric S- and R-MTPA esters and (ii) comparative (Delta delta(SR)) analysis of the 1H NMR spectral data of these two esters. By analyzing the sign of the difference in chemical shifts for a number of analogous pairs of protons (the set of Delta delta(SR) values) in the diastereomeric esters (or amides), the absolute configuration of the original carbinol (or amino) stereocenter can be reliably deduced. A typical Mosher ester analysis requires approximately 4-6 h of active effort over a 1- to 2-d period.

https://www.nature.com/articles/nprot.2007.354.pdf?proof=t

Mosher ester analysis for the determination of absolute configuration of stereogenic (chiral) carbinol carbons

The sea lamprey is an ancient, parasitic fish that invaded the Great Lakes a century ago, where it triggered the collapse of many fisheries1. Like many fishes, this species relies on chemical cues to mediate key aspects of its life, including migration and reproduction2,3. Here we report the discovery of a multicomponent steroidal pheromone that is released by stream-dwelling larval lamprey and guides adults to spawning streams. We isolated three compounds with pheromonal activity (in submilligram quantities from 8,000 l of larval holding water) and deduced their structures. The most important compound contains an unprecedented 1-(3-aminopropyl)pyrrolidin-2-one subunit and is related to squalamine, an antibiotic produced by sharks4. We verified its structure by chemical synthesis; it attracts adult lamprey at very low (subpicomolar) concentrations. The second component is another new sulfated steroid and the third is petromyzonol sulfate, a known lamprey-specific bile acid derivative. This mixture is the first migratory pheromone identified in a vertebrate and is being investigated for use in lamprey control.

Mixture of new sulfated steroids functions as a migratory pheromone in the sea lamprey

The discovery of two new components of the migratory pheromone used by sea lamprey to guide adults to spawning grounds was recently reported. These hold promise for use in a pheromone-based control program for this species, an invasive pest in the Great Lakes. Details of the structure determination of these steroidal bis-sulfates [petromyzosterol disulfate (PSDS, 2) and petromyzonamine disulfate (PADS, 3)] are described here. Pattern matching of 1H NMR data was particularly valuable. This involved comparison of spectra of the natural samples of 2 and 3 with those of appropriate steroidal analogues [e.g., petromyzonol sulfate (PS, 1, a previously known sea lamprey bile acid derivative that is a third component of the migratory pheromone), cholesterol sulfate (6), and squalamine (8)] and model compounds containing the unprecedented aminolactam substructure present in 3. The logic underlying the iterative analyses used is presented.

Details of the structure determination of the sulfated steroids PSDS and PADS : New components of the sea lamprey (Petromyzon marinus) migratory pheromone

Details of the Structure Determination of the Sulfated Steroids PSDS and PADS: New Components of the Sea Lamprey (Petromyzon marinus) Migratory Pheromone.

Feng Shao

Papers

Mosher ester analysis for the determination of absolute configuration of stereogenic (chiral) carbinol carbons

Mixture of new sulfated steroids functions as a migratory pheromone in the sea lamprey

Details of the structure determination of the sulfated steroids PSDS and PADS : New components of the sea lamprey (Petromyzon marinus) migratory pheromone

Details of the Structure Determination of the Sulfated Steroids PSDS and PADS: New Components of the Sea Lamprey (Petromyzon marinus) Migratory Pheromone.

Simultaneous vacuum-ultrasonic assisted extraction of bioactive compounds from lotus leaf