Synthesis and Acid-Catalyzed Hydrolysis of Some 3-(4-Methoxyphenyl)propyl Glucuronates

Abstract

3-(4-Methoxyphenyl)propyl D-glucuronate, 3-(4-methoxyphenyl)propyl methyl 4-O-methyl-α-Dglucopyranosiduronate, 3-(4-methoxyphenyl)propyl 1,2,3,4-tetra-O-acetyl-α-D-glucopyranuronate and 3-(4-methoxyphenyl)propyl 1,2-(S):3,5-di-O-benzylidene-α-D-glucofuranuronate were prepared as a model substances for the ester lignin-saccharide bonds. Rates of acid-catalyzed hydrolysis of the prepared compounds in 1 M HCl in acetonitrile-water 3 : 1 at 20 °C have been measured by LC-DAD analysis and it showed the low stability of the ester bonds towards acid hydrolysis.

Identification of genes encoding microbial glucuronoyl esterases

“…One unit of glucuronoyl esterase activity is defined as the amount of the enzyme deesterifying 1 μmol of 4‐nitrophenyl 2‐ O ‐(methyl 4‐ O ‐methyl‐α‐ d ‐glucopyranosyluronate)‐β‐ d ‐xylopyranoside(II) in 1 min at 30 °C [9]. The two methyl esters were generous gifts from Dr. J. Hirsch, 3‐(4‐methoxyphenyl)propyl‐methyl‐4‐ O ‐methyl‐α‐ d ‐glucopyranosiduronate(III) [14], the substrate mimicking the lignin–hemicellulose linkage, was supplied by Dr. M. Poláková (both from the Institute of Chemistry, Slovak Academy of Sciences, Bratislava, Slovakia). Formulas of all three substrates are shown in Fig.…”

“…One of the reaction parameters varied when temperature and pH optima of the enzyme were determined. Kinetic parameters of the H. jecorina enzyme for compound II and 3‐(4‐methoxyphenyl)propyl methyl 4‐ O ‐methyl‐α‐ d ‐glucopyranosiduronate (compound III) [14], were determined at pH 5.5 and 30 °C. Decomposition of both chromogenic substrates was followed by HPLC using a spectrophotometric detector as described earlier [9].…”

Glucuronoyl Esterase Screening and Characterization Assays Utilizing Commercially Available Benzyl Glucuronic Acid Ester

“…The discovery and characterization of GEs rests upon substrates that are products of laborious organic synthesis procedures, e.g., [13,14,15], thus limiting their accessibility and impeding the development and utilization of this promising class of enzymes. To broaden the scope of GE research, as well as to enhance its applicability in the sector of Industrial Biotechnology, standardized assays based on readily available substrates are required.…”

Synthesis of l-Pyranosides by Hydroboration of Hex-5-enopyranosides Revisited

“…Following this procedure known compounds were synthesized: 3a , 4a , 3b , 4b , 3c , 3e , 3f , 4f , 3h , 3i , 3j , and 3m …”

“….75 (d, J = 11.9 Hz, 1H), 4.66 (d, J = 11.9 Hz, 1H), 4.01 (dd, J = 9.2, 9.2 Hz, 1H), 3.77−3.66 (m, 4H), 3.64 (dd, J = 9.5, 3.5 Hz, 1H), 2.70 (bs, 1H), 2.06 (bs, 1H). 13 (23). To stirred suspension of compound 22 37 (1.7 g, 5.242 mmol) in MeCN (50 mL), benzaldehyde dimethylacetal (1.03 mL, 6.863 mmol) and camphorsulfonic acid (122 mg, 0.525 mmol) were added.…”