Synthesis of trimethacarb hydroxymethyl metabolites and corresponding glucoside derivatives

First Synthesis of a Series of New Natural Glucosides

“…10 Stille coupling reaction of 11 with allyltributylstannane in the presence of tetrakis-(triphenylphosphine)palladium [Pd(PPh 3 ) 4 ] and cesium fluoride (CsF) in THF gave 2-methoxy-5-(2-propenyl)phenol (12) in 84% yield. 11 According to the Reimer-Teimann reaction, treatment of 13 with NaOH solution in CHCl 3 gave 2-hydroxy-5-methoxybenzaldehyde (14) in 48% yield.…”

“…But for the coupling reaction of the aromatic aglycon this traditional Koenigs-Knorr reaction cannot afford any desired coupling product. To find a good coupling method of phenolic hydroxy group and acetobromo-α-D-glucose, different bases such as silver oxide (Ag 2 O), silver carbonate (Ag 2 CO 3 ), potassium carbonate (K 2 CO 3 ) and different solvents such as DMF, CH 2 Cl 2 , pyridine were attempted, but none of them gave the positive result. At the crucial juncture, we assumed that a stronger base would accelerate the deprotonation of the phenolic hydroxy group and water would facilitate the solubility of the deprotonated product.…”

“…A solution of 3,4,0.27 mmol) in acetone (2 mL) was slowly added to a mixture of aromatic aglycon 9, 12, 15 or 18 (0.39 mmol) and NaOH (31 mg, 0.78 mmol) pre-cooled at 5 ℃ in water (2 mL) respectively. The reaction mixture was stirred for 10 h at room temperature, then extracted with CH 2 Cl 2 (3×5 mL).…”

“…The reaction mixture was stirred for 10 h at room temperature, then extracted with CH 2 Cl 2 (3×5 mL). The organic layer was dried over anhydrous Na 2 SO 4 3 ), 4.18-4.26 (m, 2H), 4.88-4.92 (m, 1H), 5.18-5.20 (m, 1H), 5.28-5.32 (m, 2H), 5.72 (d, J＝ 8.1 Hz, 1H, GluC 1 -H), 6.07 (dt, J＝15.3, 6.3 Hz, 1H, 2'-CH＝), 6.30 (d, J＝15.3 Hz, 1H, 1'-CH＝), 6.81 (d, J＝8.1 Hz, 1H, ArH), 7.00 (d, J＝8.1 Hz, 1H, ArH), 7.14 (s, 1H, ArH);13 C NMR (CDCl 3 , 75 MHz) δ: 18.4, 20.6 (overlapping signals), 56.1, 62.1, 68.5, 71.2, 71.9, 72.6, 100.9, 112.5, 117.3, 122.3, 124.3, 130.0, 131.3, 149.6, 150.1, 169.5, 169.9, 170.5, 170.6;IR (KBr) ν: 3464, 2923, 1756, 1376, 1226, 1032 3,56.2,62.0,68.4,71.2,71.9,72.6,100.8,112.8,115.8,120.4,124.4,132.7,137.3,146.0,148.9,169.5,169.9,170.5,170.6;IR (KBr) 55.5,61.9,68.3,71.1,71.8,72.7,100.8,110.7,113.0,118.5,124.7,127.4,129.6,147.8,155.7,169.2,169.4,170.3,170.6;…”

“…2 In the Fischer glycosidation of sugars with alcohols and catalytic amounts of an acid, either the α-anomer alone or mixtures of α-and β-anomers were obtained at the high temperature range (65-140 ℃) and for long reaction time (24-72 h). 2a The classical Koenigs-Knorr method was extensively applied to the coupling reaction of the aglycon and the glycosyl halides, it is mostly used for alkyl aglycon, 3 thus alkyl glucoside 1 was synthesized by the glycosylation of the unprotected dihydroxy aglycon. But this method can not be used for aromatic aglycon in our procedure.…”