A bioinspired synthesis of the sedaxane metabolite 2 from intermediate 3 using catalytic VO(acac)2 and O2 is described. Intermediate 3 was synthesized starting from 2-bromostyrene in four steps. The inner cyclopropyl ring of 3 was assembled with trans geometry using a highly diastereoselective Nishiyama cyclopropanation, and the outer hydroxycyclopropyl ring was installed using the Kulinkovich cyclopropanation.
View Article and Find Full Text PDFWe have developed a screening protocol to identify compounds with characteristics of small molecule proteasome inhibitors using the real-time analysis of the Caenorhabditis elegans germ line. This screen is able to identify compounds that induce germ line phenotypes characteristic of a reduction in proteasome function such as changes in polarity, aberrant nuclear morphology, and stimulation of apoptosis. This basic protocol is amenable to a high throughput (96-well) format and has been used successfully to identify multiple compounds for further analysis based on structural elements from the naturally occurring compounds lactacystin and the β-lactone homologs omuralide and salinosporamide A.
View Article and Find Full Text PDFObjective: Discuss etiology of Alzheimer's disease (AD) and offer a paradigm shift-a change in basic assumptions-from present standards in clinical trials.
Data Source: PubMed search for studies into AD pathophysiology and assessment of disease progression. Searched terms: amyloid precursor protein/amyloid beta pathology, senile plaques, mitochondrial dysfunction, reactive oxygen species , advanced glycation end products, neuro-inflammation, dysfunctional microglia/astrocytes, proinflammatory cytokines, ApoE4 allele, Tau phosphorylation, Chlamydia pneumoniae, Dementia Severity Rating Scale, Clinical Dementia Rating Scale, Relative's Assessment of Global Symptomatology-Elderly, and Alzheimer's Disease Assessment Scale-cognitive.
In its crystal structure, the title compound, C(9)H(7)NO(3), forms π-stacked dimers, with a centroid-centroid distance of 3.475 (5) Å between the benzenoid and the 2,4 dicarbonyl oxazine rings. These dimers then form staircase-like linear chains through further π-stacking between the benzenoid rings [centroid-centroid distance of 3.
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