Amyloid Precursor Protein Secretases/antagonists & inhibitors; Aspartic Acid Endopeptidases/antagonists & inhibitors; Cyclopropanes/pharmacology; Enzyme Inhibitors/pharmacology; Thiazines/pharmacology; Alzheimer Disease/cerebrospinal fluid; Alzheimer Disease/drug therapy; Alzheimer Disease/metabolism; Amyloid Precursor Protein Secretases/metabolism; Amyloid beta-Peptides/cerebrospinal fluid; Amyloid beta-Peptides/metabolism; Animals; Aspartic Acid Endopeptidases/metabolism; Brain/drug effects; Brain/metabolism; Cyclopropanes/chemistry; Cyclopropanes/pharmacokinetics; Cyclopropanes/therapeutic use; Enzyme Inhibitors/chemistry; Enzyme Inhibitors/pharmacokinetics; Enzyme Inhibitors/therapeutic use; Humans; Male; Mice; Models, Molecular; Peptide Fragments/cerebrospinal fluid; Peptide Fragments/metabolism; Rats, Sprague-Dawley; Thiazines/chemistry; Thiazines/pharmacokinetics; Thiazines/therapeutic use