[Google Scholar] 16. decarboxylation gave lactone 10 in 60% yield. Aldol condensation of 10 with benzaldehyde followed by dehydration with acetic anhydride-triethylamine at 120 C offered the ,-unsaturated lactone 11 in 80% yield.16 Hydrogenation of 11 with 10% Pd/C (1 atm, 6 h) offered lactone 12 as the sole product. The task of three chiral centers, as indicated in Plan 2, was confirmed from the X-ray crystallographic analysis of 12 (Number 2). Removal of the silyl group in lactone 12 with assay.22 The IC50 ideals of 2 and 3 are 0.7 Rabbit polyclonal to SGK.This gene encodes a serine/threonine protein kinase that is highly similar to the rat serum-and glucocorticoid-induced protein kinase (SGK). nM and Vc-seco-DUBA 0.6 nM, respectively (Fig. 3A), which is Vc-seco-DUBA similar to the parent compound, L-685,458 (1). These findings have shown that incorporating BPA into Vc-seco-DUBA the P1 position and attaching a biotin tag in the C-terminus do not impact their potency for inhibition of -secretase. Second, we tested whether 3 was capable of photo-crosslinking to -secretase. HeLa cell membranes were incubated with 3 at a final concentration of 10 nM in the absence and the presence of 2 M of L-685,458 for 2.5 h. Then samples were irradiated with UV light ( 350 nm) and the labeled proteins were solubilized and isolated with streptavidin beads.4 Open in a separate window Number 3 Both 2 and 3 are potent Vc-seco-DUBA -secretase inhibitors that directly bind to Presenilin-1. A) Inhibitory potencies of compounds 2 and 3 against -secretase. B) Plan of photoaffinity labeling process. After photo-crosslinking, the biotinylated proteins were captured, eluted and analyzed by Western analysis. C) Analysis of photolabeled proteins. The photo-crosslinked proteins were resolved by SDS-PAGE and probed with PS1-NTF (1.0, CHCl3); 1H NMR (400 MHz, CDCl3): 7.38 (d, = 7.4 Hz, 2H), 7.33 (m, 4H), 7.22 (t, = 7.1 Hz, 1H), 7.17 (d, = 8.0 Hz, 2H), 5.75 (s, 1H), 4.47 (brs, 1H), 3.70 (brs, 1H), 3.93 (m, 2H), 2.80 (m, 3H), 1.38 (s, 9H), 0.94 (s, 9H), 0.01 (s, 3H), 0.00 (s, 3H); 13C NMR: 155.2, 145.1, 143.7, 135.3, 129.3, 128.1, 126.9, 126.5, 126.2, 79.5, 76.4, 53.2, 46.8, 37.2, 28.2, 25.8, 18.3, ?4.8; EIMS: 506.3 [M + Na+], HRMS (ESI) calcd for C28H41NSiO4Na: 506.2703, found 506.2698. 15. Evans Become, Rittle KE, Homnick CF, Springer JP, Hirshfield J, Veber DF. J Org Chem. 1985;50:4615. [Google Scholar] 16. Nadin A, Lopez JMS, Neduvelil JG, Thomas SR. Tetrahedron. 2001;57:1861. [Google Scholar] 17. Preparation of 13. 0.7, CHCl3); 1H NMR (400 MHz, CDCl3): 7.35C7.21 (m, 10 H), 7.15 (d, = 7.2 Hz, 2H), 7.10 (d, = 7.9 Hz, 2H), 5.77 (d, = 2.7 Hz, 1H), 4.43 (br, 1H), 4.09 (br, 1H), 3.85 (br, 1H), 3.24 (dd, = 4.0, 13.8 Hz, 1H), 2.87C2.68 (m, 4H), 2.63 (d, = 3.3 Hz, 1H, OH), 2.18 (m, 1H), 1.75 (m, 1H), 1.31 (s, 9H); 13C NMR: Vc-seco-DUBA 177.6, 155.3, 143.9, 142.5, 138.4, 135.9, 129.6, 128.8, 128.7, 128.5, 128.4, 127.5, 127.3, 127.2, 126.8, 126.7, 126.5, 79.8, 78.8, 75.9, 54.3, 43.0, 36.1, 31.6, 28.2; EIMS: 524.1 [M + Na+], HRMS (ESI) calcd for C31H35NO5Na: 524.2413, found 524.2402. 18. Fauq AH, Cherif-Ziani C, Richelson E. Tetrahedron: Asymmetry. 1998;9:2333. [Google Scholar] 19. Preparation of 14. Tert-Butyl (S)-2-(4-benzoylphenyl)-1-((2R,4R)-4-benzyl-5-oxotetrahydrofuran-2-yl) ethyl carbamate (14). To an ice-cold answer of 13 (240 mg, 0.478 mmol) in CH2Cl2 (10 mL) was added MnO2 (415 mg, 4.78 mmol). The suspension was stirred at rt. immediately. The reaction combination was filtered through celite, washed.