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Biomedical subjects

Steven V Ley

Publications and source records attributed to Steven V Ley.

At least 73 records · Page 4Linked to original sources
PubMed2003

Addition of dithiols to bis-ynones: development of a versatile platform for the synthesis of polyketide natural products.

[reaction: see text] The conjugate addition of dithiols to bis-ynones generates a versatile masked 1,3,5-triketone platform. These functional units are useful intermediates for the synthesis of oxygen-containing heterocycles commonly found in polyketide natural products. The tetrahydropyranyl fragments of the marine macrolides Lyngbouilloside and Callipeltoside A have been synthesized with use of this methodology.

Anti-Bacterial Agents↗
PubMed2003

Transfer hydrogenation using recyclable polyurea-encapsulated palladium: efficient and chemoselective reduction of aryl ketones.

A robust and recyclable palladium catalyst [Pd0EnCat] has been prepared by ligand exchange of polyurea-encapsulated palladium(II) acetate with formic acid, resulting in deposition of Pd(0) in the support material; Pd0EnCat is shown to be a highly efficient transfer hydrogenation catalyst for chemoselective reduction of a wide range of aryl ketones to benzyl alcohols.

Catalysis↗
PubMed2003

Microencapsulation of osmium tetroxide in polyurea.

[reaction: see text] Osmium tetroxide has been microencapsulated in a polyurea matrix using an in situ interfacial polymerization approach. These microcapsules have been effectively used as recoverable and reusable catalysts in the dihydroxylation of olefins

Journal Article↗
PubMed2002

Highly selective entry to the azadirachtin skeleton via a Claisen rearrangement/radical cyclization sequence.

[formula: see text] A highly diastereoselective, microwave-induced Claisen rearrangement of an appropriately substituted propargylic enol ether allows the formation of the sterically congested C8-C14 bond of azadirachtin. When combined with a radical-mediated cyclization of the corresponding allene, this sequence offers rapid entry to the framework of azadirachtin.

Journal Article↗
PubMed2002

Synthesis, structure revision, and absolute configuration of (+)-didemniserinolipid B, a serinol marine natural product from a tunicate Didemnum sp.

[structure: see text] En route to proving the absolute and relative stereochemistry, through synthesis, of (+)-didemniserinolipid B (1), the first natural serinolipid isolated from a tunicate Didemnum sp., it was discovered that the isolated natural product was in fact the 31-sulfate configured 8R,9R,10R,13S,30S. This structural reassignment was only possible after the development of a microwave-assisted method for the sulfation of unreactive hydroxyl groups.

Animals↗
PubMed2002

Analytical construct resins for analysis of solid-phase chemistry.

Rapid and unambiguous analysis of reactions performed on resin supports can be achieved by using "analytical constructs". These resins allow the synthesis of materials using solid-phase methods in the usual manner, but they also contain functionality enabling cleavage of analytically enhanced derivatives of the resin-bound products. This is possible due to the use of two linkers bound in series to the polymer. Cleavage at the first linker yields the products attached to an analytical enhancer that facilitates detection. Orthogonal cleavage at the second linker yields the desired products in the usual manner.

Coloring Agents↗
PubMed2002

The total synthesis of the annonaceous acetogenin, muricatetrocin C.

The total synthesis of the potential antitumour agent muricatetrocin C has provided an ideal stage for the exploitation and development of new chemistry. A convergent synthetic strategy has been realised incorporating three distinct pieces of methodology, these include a highly diastereoselective hetero-Diels-Alder reaction to construct the butenolide terminus, an oxygen to carbon rearrangement to install the trans-2,5-disubstituted tetrahydrofuran ring and a spatial desymmetrisation process to afford the anti-diol unit.

4-Butyrolactone↗