A straight tip: With tip‐enhanced Raman spectroscopy (TERS), chemical and topographical information with nanometric resolution below the diffraction limit of soft biological samples such as bacteria can be gained simultaneously at short measuring times. This noninvasive technique opens new ways for the investigation of many problems in biology and biomedicine.
Synthesis general. Solvents were obtained from SDS and are synthetic grade. Reagents were bought form Aldrich Chemical Co. or AlfaAesar Chemical Co. NMR spectra were measured from CDCl 3 solutions of the samples using a Bruker DPX 400 spectrometer or a JEOL ECS400 spectrometer, with TMS as an internal standard. Syntheses of compounds 5 24b , 6, 10 and 14 31 have been published elsewhere. Scheme S1. Synthesis of ketoximes 10-13 from [2.2]paracyclophane. General procedure for the synthesis of ketones 7-9 [2.2]Paracyclophane (1 eq.) is dissolved in dichloromethane (c=0.1 mol.L-1), stirred and cooled at 0° in an salt-ice bath. The acid chloride (2.1 eq.) and aluminum chloride (1.75 eq.) are suspended in dichloromethane (c=1 mol.L-1), cooled at 0°C and added quickly to the [2.2]paracyclophane solution under rapid stirring. Reaction mixture is maintained at 0°C for 15 min, pored onto ice and vigorously stirred until the organic layer becomes colorless. Diethyl ether is added until the organic layer becomes less dense than water. The organic layer is separated, washed twice with a saturated NaHCO 3 aqueous solution and finally with a a saturated NaCl aqueous solution. The organic layer is dried on MgSO 4 and the solvents are removed under reduced pressure. The crude product is purified by column chromatography on SiO 2. Elution petroleum ether/dichloromethane 3:2 v/v to remove the unreacted
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