Kelly G. Sprankle

Identification of N-(5-tert-Butyl-isoxazol-3-yl)-N′-{4-[7-(2-morpholin-4-yl-ethoxy)imidazo[2,1-b][1,3]benzothiazol-2-yl]phenyl}urea Dihydrochloride (AC220), a Uniquely Potent, Selective, and Efficacious FMS-Like Tyrosine Kinase-3 (FLT3) Inhibitor

Treatment of AML patients with small molecule inhibitors of FLT3 kinase has been explored as a viable therapy. However, these agents are found to be less than optimal for the treatment of AML because of lack of sufficient potency or suboptimal oral pharmacokinetics (PK) or lack of adequate tolerability at efficacious doses. We have developed a series of extremely potent and highly selective FLT3 inhibitors with good oral PK properties. The first series of compounds represented by 1 (AB530) was found to be a potent and selective FLT3 kinase inhibitor with good PK properties. The aqueous solubility and oral PK properties at higher doses in rodents were found to be less than optimal for clinical development. A novel series of compounds were designed lacking the carboxamide group of 1 with an added water solubilizing group. Compound 7 (AC220) was identified from this series to be the most potent and selective FLT3 inhibitor with good pharmaceutical properties, excellent PK profile, and superior efficacy and tolerability in tumor xenograft models. Compound 7 has demonstrated a desirable safety and PK profile in humans and is currently in phase II clinical trials.

Solid-phase synthesis of a library of functionalized aminodiol scaffolds

A combinatorial library motif has been developed based on orthogonally protected aminodiol scaffolds. Amine functionality was derivatized by commercially available electrophiles including carboxylic acids, sulfonyl chlorides, isocyanates, and aldehydes. A hydroxyl moiety was converted to a carbamate linkage, allowing a variety of amines to be incorporated. The scaffold was anchored to TentaGel at the second hydroxyl via a succinyl linker, which was hydrolyzed by mild aqueous basic conditions. The method was used to make a library of about 17,000 different members in mixtures of 5 per sample.

An Efficient and Scalable Synthesis of Arabinosylguanine and 2′-Deoxy-2′-Fluoro-guanosine

Abstract An efficient conversion from commercially available 2, 6-diaminopurine-2′, 3′, 5′-tri-O-benzyl arabinoside to arabinosylguanine and its further transformation to 2′-deoxy-2′-fluoro-guanosine is outlined. This process has been used to produce more than one hundred grams of final product.