Synthesis, characterization, and initial membrane binding properties of mono- and gemini-decyl-chain lumazines

MARIA JOSÉ SOSA; MARIANA VIGNONI; JOSÉ LUIS FONSECA; PATRICIA SCHILARDI; MARIA NOEL URRUTIA; HELENA JUNQUEIRA; MAURICIO S. BAPTISTA; ROSANGELA ITRI; NILUKSHA WALALAWELA; GOUTAM GHOSH; ANDRÉS H. THOMAS; ALEXANDER GREER

Filadelfia, Pensilvania, Estados Unidos

Congreso; 259th American Chemical Society (ACS) National Meeting & Exposition.; 2020

American Chemical Society (ACS)

In an effort to tune fluorescent vs. photosensitizer properties in biomembranes, decyl-​chain and bis-​decyl-​chain [-​(CH2)​9CH3]​n (n = 1 and 2) lumazine [pteridine-​2,​4(1,​3H)​-​dione] conjugates are being synthesized and characterized. A nucleophilic substitution (SN2) reaction with iododecane and K2CO3 was used for the coupling of the decyl chain to the N1 and N3 sites. Evidence is pointing to two main products, namely, 3-​decylpteridine-​2,​4(1,​3H)​-​dione and 1,​3-​didecylpteridine-​2,​4(1,​3H)​-​dione based on NMR (1H, 13C, HSQC, HMBC)​, HPLC, TLC, and UV-​VIS data. Measurements of fluorescence quantum yields and the degree of interaction of these lumazines with biomembranes are being studied with large unilamellar vesicles (LUVs) as a biomimetic system. Data on their binding consts. and ability to photooxidize the vesicles is forthcoming. Our study aims to expand on a wider series of lipophilic, photooxidatively active lumazines.