The Caribbean region is a hotspot of biodiversity (i.e., algae, sponges, corals, mollusks, microorganisms, cyanobacteria, and dinoflagellates) that produces secondary metabolites such as polyketides polypropionates. Polyketides are diverse class natural products synthesized by organisms through biosynthetic pathway catalyzed polyketide synthase (PKS). This group compounds subdivided into fatty ...

Polyalcohol is an environmentally friendly anti-collapse lubricant commonly used in water-based drilling fluids. It generally composed of the single polyether or polyol, but its lubricity and inhibition can’t satisfy application current fluid systems well. Consequently, laboratory has carried out research on compound polyalcohol. The samples are mixed with lauryl polyether, nonylphenol Tween 80...

In the course of our studies concerning the derivatization of the polyether ionophore nigericin1'2) we observed a dependence of the antibacterial activity on the counter ion at C-l,3) which prompted us to investigate if related effects can also be found for other polyethers and indications. Salinomycin (1), for example is another important polyether4'5) which is produced in combination with rel...

Poly(1,3,4-oxadiazole-ether) with reactive carboxylic acid pendants was synthesized from solution polymerization via nucleophilic displacement polycondensation among 2,5-bis(4-fluorophenyl)-1,3,4-oxadiazole (BFPOx) and 4,4'-bis(4-hydroxyphenyl) valeric acid (BHPA). Without altering the polymeric segments, benzimidazole modified poly(1,3,4-oxadiazole-ether)s were prepared by varying stoichiometr...

The lithium diisopropylamide-mediated 1,2-elimination of 1-bromocyclooctene to provide cyclooctyne is investigated using approximately 50 potentially hemilabile polyethers and amino ethers. Rate laws for selected ligands reveal chelated monomer-based pathways. The dependence of the rates on ligand structure shows that anticipated rate accelerations based on the gem-dimethyl effect are nonexiste...

Noboritomycins A and B, two new polycyclic ionophoric polyethers were isolated from a strain of Streptomyces noboritoensis. The crystal structure and absolute configuration of noboritomycin A were established by X-ray analysis of its silver salt C43/63O14Ag. Noboritomycin A is the first metabolic polyether possessing two carboxylic acid functions on the carbon backbone (C-31), namely a free aci...