If http://www.selleckchem.com/products/Imatinib-Mesylate.html different Inhibitors,Modulators,Libraries bacteria processed ester-protected AI-2 analogs differently, then one could selectively modulate the activity of specific bacteria in an ecosystem via the use of differently protected AI-2 analog.Figure 1.Structure of AI-2 dimer.2.?Experimental Section2.1. Synthesis of Diazocarbonyls2.1.1. Generation of DiazomethaneDiazomethane was generated from Diazald? (Sigma-Aldrich, St. Louis, MO, USA) using a diazomethane generator apparatus (Sigma-Aldrich, Oberkochen, Germany), following the protocol provided by Sigma-Aldrich (Oberkochen, Germany). Briefly, a solution of Diazald? (5 g) in diethyl ether (45 mL) was slowly added to a solution of KOH (5 g) in mixed solvent (water (8 mL) and ethanol (10 mL)) at 65 ��C over 20 min.
The generated diazomethane and the diethyl ether solvent distilled and was trapped in a collecting vessel using a dry ice/isopropanol bath to give diazomethane as a solution in diethyl ether (ca. 0.4�C0.5 M).2.1.2. Addition of Diazomethane to Acyl ChloridesTo a solution of diazomethane (3 equiv.) in diethyl ether was added an acyl chloride (1 equiv.) dropwise Inhibitors,Modulators,Libraries at 0 ��C. The resulting solution was allowed to stir for another 2 h and warmed up gradually to room temperature. The solvent was removed under vacuum and the diazocarbonyl Inhibitors,Modulators,Libraries residue (a yellow liquid) was used for the next step without further purification.2.2. Inhibitors,Modulators,Libraries Synthesis of DiazodiolsDBU (0.16�C0.20 equiv.) and 2-(tert-butyldimethylsilyloxy) acetaldehyde (1�C1.5 equiv.) were added to a solution of the crude diazocarbonyl (1 equiv.) in anhydrous acetonitrile (0.2 M).
The reaction was stirred at room temperature under nitrogen for 4�C8 h and monitored by TLC. Upon disappearance of starting material, the reaction GSK-3 was quenched with sodium bicarbonate. The organic layer was extracted with dichloromethane (3 �� 20 mL) and dried with magnesium sulfate. The solvent was evaporated under reduced pressure. To a solution of crude product in anhydrous tetrahydrofuran at 0 ��C, TBAF was added (1�C2 equiv.). The solution was allowed to warm to room temperature and stirred for 1�C3 h under nitrogen. The solvent was evaporated, and the crude product was purified by column chromatography. The products eluted as yellow oils using 1:3 to 3:2 ethyl acetate/hexane as the mobile phase.2.3. Synthesis of Ester Protected Diazo CompoundsTo a stirring solution of diazodiol (1 equiv.
) catalytic 4-dimethylaminopyridine (DMAP) and suspended 4 ? molecular sieves in dichloromethane (DCM) was added the requisite selleck anhydride. The reaction was allowed to gently stir at room temperature for 2�C4 h until complete disappearance of starting material was indicated by TLC. The crude reaction mixture was filtered washed with saturated aqueous NaHCO3 solution and the organic phase was extracted with more DCM.