ABSTRACT
We report herein a novel series of difluoropiperidine acetic acids as modulators of gamma-secretase. Synthesis of 2-aryl-3,3-difluoropiperidine analogs was facilitated by a unique and selective beta-difluorination with Selectfluor. Compounds 1f and 2c were selected for in vivo assessment and demonstrated selective lowering of Abeta42 in a genetically engineered mouse model of APP processing. Moreover, in a 7-day safety study, rats treated orally with compound 1f (250mg/kg per day, AUC(0-24)=2100microMh) did not exhibit Notch-related effects.
Subject(s)
Acetates/chemistry , Amyloid Precursor Protein Secretases/metabolism , Fluorine/chemistry , Piperidines/chemistry , Acetates/chemical synthesis , Acetates/pharmacokinetics , Amyloid beta-Peptides/genetics , Amyloid beta-Peptides/metabolism , Animals , Diazonium Compounds/chemistry , Disease Models, Animal , Mice , Mice, Transgenic , Peptide Fragments/genetics , Peptide Fragments/metabolism , Piperidines/chemical synthesis , Piperidines/pharmacokinetics , Rats , Receptors, Notch/metabolismABSTRACT
[reactions: see text] One-pot total syntheses of the quinazolinobenzodiazepine alkaloids sclerotigenin (1), (+/-)-circumdatin F (2), and (+/-)-asperlicin C (3) via novel microwave-assisted domino reactions were achieved in 55%, 32%, and 20% yields, respectively, from commercially available starting materials. A two-step total synthesis of (+/-)-benzomalvin A (4) was accomplished with an overall yield of 16%. Additionally, analogues of circumdatin E were synthesized via the three-component one-pot sequential reactions promoted by microwave irradiation. Finally, a two-step formal total synthesis of (+/-)-asperlicin E (5) was also realized by using this microwave-assisted protocol.
Subject(s)
Alkaloids/chemical synthesis , Benzodiazepines/chemical synthesis , Microwaves , Quinazolines/chemical synthesis , Benzodiazepinones/chemical synthesis , Methods , Pyrimidinones/chemical synthesisABSTRACT
A microwave-promoted three-component one-pot reaction has been developed to provide access to the core pyrazino[2,1-b]quinazoline-3,6-dione (1) scaffold, which is common to several families of alkaloids with significant biological activities. By adapting this synthetic strategy through the use of selected Boc-amino acids and amino acid esters, we have accomplished highly efficient and concise total syntheses of glyantrypine (2), fumiquinazoline F (3), and fiscalin B (5), achieving overall yields of 55, 39, and 20%, respectively.
