Synthesis and fungicidal activity of N-thiazol-4-yl-salicylamides, a new family of anti-oomycete compounds.

A novel class of experimental fungicides has been discovered, which consists of special N-thiazol-4-yl-salicylamides. They originated from amide reversion of lead structures from the patent literature and are highly active against important phytopathogens, such as Phytophthora infestans (potato and tomato late blight), Plasmopara viticola (grapevine downy mildew) and Pythium ultimum (damping-off disease). Structure-activity relationship studies revealed the importance of a phenolic or enolic hydroxy function in the β-position of a carboxamide.

Biology-oriented synthesis of stereochemically diverse natural-product-derived compound collections by iterative allylations on a solid support.

A strategy aiming at the introduction of stereocenters into polymer-bound natural-product-derived and -inspired compound collections is presented. Treatment of immobilized aldehydes with Brown's pinene-derived allylboranes results in the stereoselective formation of homoallylic alcohols with up to 89 % ee (ee=enantiomeric excess). Subsequent iterative ozonolysis-allylation sequences with up to three allylations on a solid support give access to 1,3-polyols with different relative configurations.

Stereocomplementary synthesis of a natural product-derived compound collection on a solid phase.

Enantiocomplementary allylation of solid phase-bound aldehydes gives rise to a natural product-derived compound collection, including all stereoisomers of cryptocarya diacetate.

A total synthesis of guanacastepene C.

A total synthesis of the structure corresponding to the novel tricyclic diterpene guanacastepene C has been realized in which a Knoevenagel cyclization serves as a key step to annulate the six-membered C-ring on a stereochemically secured bicyclic hydroazulene precursor.

Studies toward the total synthesis of diterpene antibiotic guanacastepene A: construction of the hydroazulenic core.

[reaction: see text] As a part of studies aimed toward the total synthesis of biologically important natural product guanacastepene A of contemporary interest, a new and concise route to a fully functionally endowed hydroazulenic core is delineated. The strategy involves the building of the requisite stereochemical features on a endo-tricyclo[5.2.