Keith M. Wilcoxen

Synthesis of fluorinated olefins via the palladium catalyzed cross-coupling reaction of 1-fluorovinyl halides with organoboranes

Abstract The palladium catalyzed cross-coupling reaction of 1-fluorovinyl halides 1–4 with organoboranes proceeds under Suzuki conditions with retention on configuration to give 1-substituted 1-fluoroolefins 6–8 in good to excellent yields.

Palladium/Copper (I) halide-cocatalyzed stereospecific coupling of 1-fluorovinylstannanes with aryl iodides and acyl chlorides

Abstract Cross-coupling of 1-fluorovinylstannanes with aryl iodides or acyl chlorides, cocatalyzed by palladium and copper (I) iodide proceeded under mild conditions to give substituted fluoro olefins and α-fluoro-α,β-unsaturated ketones, respectively, in good yields with retention of configuration.

New methods for the synthesis of fluoroolefins via the palladium catalyzed cross-coupling reaction of 1-fluorovinyl halides with organoboranes and organostannanes

Abstract The palladium catalyzed cross-coupling reaction of 1-fluorovinyl halides with organoboranes and organostannanes provide two new facile methods to 1-substituted 1-fluoroolefins. The reactions proceed with retention of configuration in good to excellent yields.

Initial Structure–Activity Relationship Studies of a Novel Series of Pyrrolo[1,2-a]pyrimid-7-ones as GnRH Receptor Antagonists

Initial SAR studies on 1-aminomethyl-2-aryl-3-cyano-pyrrolo[1,2-a]pyrimid-7-one-6-carboxylates as human GnRH receptor antagonists were discussed. 2-(2-Methylaminoethyl)pyridine was discovered to be a key feature for generating active compounds. The best compound from the series had 25 nM (K(i)) binding affinity to human GnRH receptor.

Synthesis and initial structure–Activity relationships of a novel series of imidazolo[1,2-a]pyrimid-5-ones as potent GnRH receptor antagonists

SAR studies of 2-arylimidazolo[1,2-a]pyrimid-5-ones 10a-m, which were derived from initial lead 3a, resulted in the discovery of a series of potent nonpeptide human GnRH receptor antagonists. Compounds with good potency (e.g., 10e, K(i)=7.5 nM) were prepared by introduction of a 2-(2-pyridyl)ethyl at the basic nitrogen and a 3-pentyl ester at the 6-position of the bicyclic core.

A Novel Synthesis of 2-Arylpyrrolo[1,2-a]pyrimid-7-ones and Their Structure–Activity Relationships as Potent GnRH Receptor Antagonists

In the process of developing GnRH receptor antagonists, a novel base-catalyzed cyclization of compounds 5a-b was discovered, which led to the formation of the 2-aryl pyrrolo[1,2-a]pyrimid-7-one core structures 6a-b. These intermediates were further modified at positions 1, 2, 4 and 6 to afford a series of potent GnRH antagonists with low nanomolar K(i) values.

Design, synthesis and structure-activity relationships of novel imidazolo[1,2-a]pyrimid-5-ones as potent GnRH receptor antagonists.

SAR studies of lead GnRH receptor antagonists 2a and 2b reported earlier resulted in the discovery of compound 10b which showed much higher potency (K(i)=4.6 nM, compared with 2b, K(i)=230 nM) in which the 7-position of the imidazolo[1,2-a]pyrimidone core was substituted with a methyl group, and the ester at the 6-position was replaced by the 3-methoxyphenyl group.

A convenient one-pot synthesis of 4-amino-3-arylpyrazoles from α-phthaloylaminoacetophenones

Abstract Condensation of α-phthaloylaminoacetophenones 1a-c with N,N-dimethylformamide dimethyl acetal afforded the novel enamines 3a-c . Cyclization of 3 with hydrazine, alkylhydrazine or phenylhydrazine salts ( 4a-d ) gave 4-phthaloylamino-3-arylpyrazoles 7–9 in high yields. Deprotection of 7–9 was accomplished with hydrazine to provide 4-amino-3-arylpyrazoles 5 in good yields.

Synthesis and SAR of 8-Arylquinolines as potent corticotropin-Releasing factor1 (CRF1) receptor antagonists

A series of 4-substituted 8-aryl-2-methylquinolines 4 was designed and synthesized as highly potent antagonists for the human CRF(1) receptor. This series of compounds displayed parallel SAR to other bicyclic systems such as pyrazolo[1,5-a]pyrimidines, with several compounds possessing low nanomolar binding affinity. In addition to the high potency, the basicity of this 4-aminoquinoline core may offer CRF(1) antagonists with lower lipophilicity.

Quinoline-carboxylic acids are potent inhibitors that inhibit the binding of insulin-like growth factor (IGF) to IGF-binding proteins.

4-benzylquinolines 5, based on a series of isoquinolines 1, were prepared and tested as inhibitors of the IGF/IGFBP-3 complex based on their ability to displace IGF-I from its binding to IGF-binding protein-3. SAR studies on the 6,7-dihydroxy moiety of the quinoline 5a showed that the catecol moiety could be replaced with other functional groups. Computational modeling of the 5a/mini-IGFBP-5 complex revealed the possible binding site of 5a on IGFBP-5.