[EN] COMPOUNDS, A PROCESS FOR THEIR PREPARATION AND THEIR USE AS DYES AND PIGMENTS [FR] NOUVEAUX COMPOSES, LEUR PROCEDE DE PREPARATION ET LEUR UTILISATION EN TANT QUE COLORANTS ET PIGMENTS
Oxazolone analogs as amyloid aggregation inhibitors and for the treatment of alzheimer's disease and disorders related to amyloidosis
申请人:——
公开号:US20040180943A1
公开(公告)日:2004-09-16
Disclosed are compounds of the Formula I
1
and their use in a method of inhibiting the aggregation of amyloid proteins and in a method of imaging amyloid deposits.
揭示了Formula I1的化合物及其在抑制淀粉样蛋白聚集的方法和成像淀粉样沉积的方法中的应用。
SULFUR- AND N-ACYL CARBONYL OXYGEN-ASSISTED HETEROLYSIS OF THE C(=O)–S BOND IN EXCITED-STATE (Z)-N-ACYL-α-DEHYDRO(1-NAPHTHYL)ALANINE THIOESTERS
Irradiation of the title thioesters (Z)-1 in nitrogen-saturated 1,2-dichloroethane at wavelengths greater, than 280 nm was found to afford (Z)-4-(1-naphthylmethylene)-5(4H)-oxazolone derivatives (Z)-2, (E)-2, alkyl-substituted thiols 3, and (E)-1 without forming any thio-radical-derived products. An analysis of the substituent and solvent effects on the reactivity of 1 and the product distribution demonstrated that the heterolytic C(=O)-S bond cleavage products 2 and 3 are not derived from the long-lived acylium and thiolate ions but from the protonated oxazolone/thiolate ion pair. The latter intermediates were assumed to be formed by the sulfur-assisted nucleophilic addition of the N-acyl carbonyl oxygen to the thioester carbonyl carbon in the excited state, followed by the elimination of the thiolate ion from the resulting adducts.