... Tetrahedron. Volume 64, Issue 37, 8 September 2008, Pages 8638–8641. ... Samples (250 μL) were taken at intervals, brought to pH 1 by addiction of 5% HCl, extracted with an equal volume of ethyl acetate and analysed by TLC (80% AcOEt/MeOH) and HPLC/DAD in the ...