The discovery and optimization of a novel series of aminoisoquinolines as potent, selective, and efficacious inhibitors of the mutant B-Raf pathway is presented. The N-linked pyridylpyrimidine benzamide 2 was identified as a potent, modestly selective inhibitor of the B-Raf enzyme. Replacement of the benzamide with an aminoisoquinoline core significantly improved kinase selectivity and imparted favorable pharmacokinetic properties, leading to the identification of 1 as a potent antitumor agent in xenograft models.

A series of N-acetylated, non-alpha, aromatic amino acids was prepared and shown to promote the absorption of recombinant human growth hormone (rhGH) from the gastrointestinal tract. Seventy compounds in this family were tested in vivo in rats. Of the compounds tested, 4-[4-[(2-hydroxybenzoyl)amino]phenyl]butyric acid was identified as a preclinical candidate and was used to demonstrate the oral delivery of rhGH in primates. A significant positive correlation was found between the relative log k' of the delivery agents, as determined by HPLC on an immobilized artificial membrane (IAM) column, and serum rhGH concentrations following oral or colonic dosing in rats. Structure-activity relationships have also been developed on the basis of electronic effects and hydrogen-bonding characteristics of the aromatic amide substituents.

A series of N-acylated alpha-amino acids were synthesized and shown to improve the oral delivery of two protein drugs, salmon calcitonin (sCT) and interferon-alpha. Forty-five compounds in this series were tested in vivo in rats and primates. A significant positive correlation was found between the log P of the acylated amino acids and the decrease in serum calcium following oral dosage of sCT in rats. Such a correlation was not found for interferon-alpha. These derivatized amino acids only weakly inhibited the activity of trypsin or leucine aminopeptidase. Histological examinations of rat intestinal tissue after oral dosing of acylated amino acid/protein combinations revealed no detectable pathology.

A series of benzoylated and phenylsulfonylated amino acids are novel, low molecular weight, self-assembling molecules. At low pH, these compounds form microspheres that dissolve readily under neutral conditions. In a given synthetic series, those molecules with low aqueous solubility formed microspheres more readily than did the molecules possessing high water solubility, suggesting that the hydrophobicity of these compounds contributes to the ability to form microspheres. In addition, molecular modeling studies on selected compounds have shown that microsphere formation may depend also on various aromatic ring and dipole-dipole interactions, which could effect the extent and types of favorable stacking conformations between molecules. The microspheres prepared from these compounds have been used to effect the oral delivery of salmon calcitonin, a model protein drug, in both rodents and primates.

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