A Convenient Method for the Synthesis of Dehydroquinic Acid

Abstract

A convenient synthesis of dehydroquinic acid and its corresponding methyl ester are described. Protection of the trans diol of quinic acid, followed by PCC oxidation, gave fully protected dehydroquinic acid. This gave methyl dehydroquinate on mild acid catalyzed hydrolysis. Ester hydrolysis then gave potassium dehydroquinate which was treated with amberlite to afford dehydroquinic acid.

First diastereoselective synthesis of methyl caffeoyl- and feruloyl-muco-quinates

“…Oxidation of 9 with PCC followed by reduction with sodium triacetoxyborohydride yielded the protected muco-quinic acid 10 in improved yield (85% yield) 23 compared to the Mitsunobu reaction and Cs salt (50% yield). 21 After the oxidation-reduction sequence we obtained a 9 : 1 mixture of diastereomers, as judged by the integrals in the crude 1 H-NMR spectrum (91% yield), which on recrystallisation gave 85% of the inverted muco-isomer 10, whose structure could be confirmed by single crystal X-ray analysis (Table 1 and Fig.…”

“…1). 23 The diastereoselectivity of the reduction step can be rationalised by assuming interaction of the borohydride reagent with the free 1-OH alcohol followed by hydride delivery from the side of the 1-OH alcohol to produce an equatorially oriented 3-OH.…”

Rational Design, Synthesis, and Evaluation of Nanomolar Type II Dehydroquinase Inhibitors

“…Synthesis of 3‐Dehydroquinate . 3‐Dehydroquinate was synthesised (as the potassium salt) from (−)‐quinic acid using the method described by Le Sann et al 24. Calibration of 3‐dehydroquinate solutions (in water) were determined from the absorbance difference at 234 nm resulting from the total conversion of an aliquot of 3‐dehydroquinate to 3‐dehydroshikimate by 1 μL of S. coelicolor type II dehydroquinase (5.1 mg mL −1 ) using the kinetic assay described below.…”

Design and Structural Analysis of Aromatic Inhibitors of Type II Dehydroquinase from Mycobacterium tuberculosis

“…The residue was purified by column chromatography, eluting with 3:17 v/v EtOAc/PE, to afford the title compound 23 as a white crystalline solid (3.32 g, 66 %); mp: 76-77 8C (lit. : [41] 76-77 8C); + . These data are in agreement with those previously reported.…”

“…The combined organics were washed with saturated brine (20 mL), dried over Na 2 SO 4 , filtered, and concentrated under reduced pressure. The residue was purified by flash silica chromatography (Biotage Isolera), 10 g column, 12 Synthesis of 3-dehydroquinate (1): 3-Dehydroquinate 1 was synthesized (as the potassium salt) from (À)-quinic acid using the method described by Le Sann et al [41] Calibration of 3-dehydroquinate solutions (in H 2 O) were determined from the absorbance difference at l 234 nm resulting from the total conversion of an aliquot of 3-dehydroquinate to 3-dehydroshikimate by 1 mL of S. coelicolor type II dehydroquinase (5.1 mg mL À1 ) using the kinetic assay A described below. Enzyme purification M. tuberculosis type II dehydroquinase was purified as described previously.…”