PRMT5, a type 2 arginine methyltransferase, has a critical role in regulating cell growth and survival in cancer. With the aim of developing MTA-cooperative PRMT5 inhibitors suitable for MTAP-deficient cancers, herein we report our efforts to develop novel "MTA-cooperative" compounds identified through a high-throughput biochemical screening approach. Optimization of hits was achieved through structure-based design with a focus on improvement of oral drug-like properties.
View Article and Find Full Text PDFIn vitro metabolism studies of the spleen tyrosine kinase inhibitors AZ-A and AZ-B identified four unusual metabolites. M1 (mass-to-charge ratio 411) was formed by both molecules and was common to several analogs (AZ-C to AZ-H) sharing the same core structure, appearing to derive from the complete loss of a pendent 3,4-diaminotetrahydropyran ring and pyrazole ring cleavage resulting in a nonobvious metabolite. M2-M4 were formed by AZ-A and a subset of the other compounds only and apparently resulted from a sequential loss of H from parent.
View Article and Find Full Text PDFThe preparation of bridged benzo[1,5]oxazocines and benzo[1,4]diazepines is demonstrated from simple aniline and aldehyde starting materials. A one-pot condensation/6π electrocyclization is followed by an intramolecular trapping of the 2,3-dihydroquinoline intermediate by nitrogen or oxygen nucleophiles to give bridged seven- and eight-membered products. Using 3-hydroxypyridinecarboxaldehydes results in a stable zwitterionic structure that can undergo a diastereoselective reduction under hydrogenative conditions.
View Article and Find Full Text PDFIn this article, we report the discovery of a series of pyrimidopyridones as inhibitors of IRAK4 kinase. From a previously disclosed 5-azaquinazoline series, we found that switching the pyridine ring for an N-substituted pyridone gave a novel hinge binding scaffold which retained potency against IRAK4. Importantly, introduction of the carbonyl established an internal hydrogen bond with the 4-NH, establishing a conformational lock and allowing truncation of the large basic substituent to a 1-methylcyclopyl group.
View Article and Find Full Text PDFHerein we report the preparation of 2'-deoxy-2'-spirocyclopropylcytidine via an alternative cyclopropanation reaction starting from γ-silyl tertiary alcohols. Activation of the hydroxyl function with thionyl chloride in the presence of 4-DMAP allows the ring-closing step under mild conditions. Participation of the uracil moiety in the cyclization step is proposed.
View Article and Find Full Text PDFPim kinases have been targets of interest for a number of therapeutic areas. Evidence of durable single-agent efficacy in human clinical trials validated Pim kinase inhibition as a promising therapeutic approach for multiple myeloma patients. Here, we report the compound optimization leading to GDC-0339 (16), a potent, orally bioavailable, and well tolerated pan-Pim kinase inhibitor that proved efficacious in RPMI8226 and MM.
View Article and Find Full Text PDFHighly functionalized aldol-type products bearing a β-quaternary center and a stereoselectively controlled γ-hydroxy function are readily prepared by the diastereoselective addition of an allylic zinc reagent embedded in an isoxazole ring to various aromatic and heteroaromatic aldehydes, in the presence of Lewis acids, such as MgCl2 or LaCl3⋅2 LiCl. After reductive cleavage of the N-O bond by using Fe, NH4Cl, aldol-type products bearing a stereocontrolled β-quaternary center and a γ-hydroxy group were observed. The benzylic reactivity of the isoxazolylmethylzinc reagent towards other electrophiles, such as acid chlorides, aryl and allylic halides, as well as aldehydes in the presence of BF3⋅OEt2 are also described.
View Article and Find Full Text PDFA general, transition-metal-free, highly stereoselective cross-coupling reaction between glycosyl bromides and various arylzinc reagents leading to β-arylated glycosides is reported. The stereoselectivity of the reaction is explained by invoking anchimeric assistance via a bicyclic intermediate. Stereochemical probes confirm the participation of the 2-pivaloyloxy group.
View Article and Find Full Text PDFA new Fe- or Co-catalyzed Cl/Zn-exchange reaction allows the direct transformation of aryl, heteroaryl, and also alkyl chlorides into the corresponding zinc reagents. The method tolerates functional groups such as a nitrile or an ester. Remarkably, secondary and tertiary alkyl chlorides are suitable substrates for the Cl/Zn exchange.
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