Využití Pd-katalyzovaných reakcí v syntéze laktonů

Abstract

V ramci teto disertačni prace byla vyvinuta metodika připravy 3,6- disubstituovanych pyranonů a bylo připraveno 15 finalnich laktonů, u kterych byla pote zkoumana jejich cytostaticka a antifungalni aktivita. Kličovymi kroky připravy latek byla Yamaguchi-Hiraova alkylace, hydroaluminace nasledovana jodaci a Pd-katalyzovana karbonylativni laktonizace. Žadna z cilovych latek nevykazovala cytostatickou ani antifungalni aktivitu, což je vzhledem k vyznamne antifugalni aktivitě butenolidovych analogů překvapive. V dalši časti je popsan vyvoj syntezy 3-monosubstituovanych pyranonů. Vyvinuty postup využiva jako vychozi latky 5,6-dihydro-2H-pyran-2-onu, ktery je v dalšim kroku převeden na 3-jod-5,6- dihydro-2Hpyran- 2-on. Kličovym krokem je pak nasledny Pd-katalyzovany Suzukiho coupling. V posledni časti je popsana připrava několika derivatů α- a β-substituovanych-γ- alkylidenpentenolidů. Cilove latky se vyznačovaly vyznamnou cytostatickou aktivitou (IC50 < 5 μmol/L) vůči všem testovanym nadorovym liniim (CCRF-CEM, HeLa S3, HT 29, HL 60, L 1210).

Within the framework of this Thesis, a method fot the preparation of 3,6- disubstituted pyranones was developed and 15 final lactones were synthesized, and their cytostatic and antifungal activity was investigated. Principal steps in the preparation of the compounds were Yamaguchi-Hirao alkylation, hydroalumination followed by iodation and Pd- catalyzed carbonylative lactonization. None of the target compounds displayed interesting cytostatic or antifungal activity (IC50 < 10 μmol/L), which was suprising given the significant antifungal activity of analogous butenolides. The development of the synthesis of 3- monosubstituted pyranones is described next. Our strategy is based on the use of 5,6-dihydro-2H- pyran-2-one as the starting material, which was converted into the 3-iodo-5,6-dihydro-2H- pyran-2-one in one step. The key step of the synthesis was Pd-catalyzed Suzuki coupling. Finally, the preparation of α- and β-substituted-γ-alkylidenepentenolides is described. The target compounds exhibited significant cytostatic activity (IC50 < 5 μmol/L) against all tested tumor cells (CCRF-CEM, HeLa S3, HT 29, HL 60, L 1210).