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EXAMPLE 27 Synthesis of p-aminophenylacetic acid-N-L-rhamnoside: Into ethanol, 1.51 g of p-aminophenylacetic acid and 1.82 g of <strong>[10030-85-0]L-<strong>[10030-85-0]rhamnose monohydrate</strong></strong> were dissolved, and after adding 54 mg of ammonium chloride into the solution, the mixture was heated for 10 min under a reflux condenser in a stream of gaseous nitrogen. After filtering the reaction mixture by a sheet of filter paper, the filtrate was cooled. Then, the deposited crystals were collected by filtration and dried. The yield was 1.67 g. Purified p-aminophenylacetic acid-N-L-rhamnoside was obtained by recrystallizing the dried crystals with ethanol.
With hydrogenchloride; In water; ethyl acetate; acetone;
EXAMPLE 12 3,6-Di-(alpha-L-rhamnopyranosyl-amino)-10-N-methylacridinium chloride Under stirring 3.64 g (1.4*10-2 mole) of 3,6-diamino-10-N-methyl-acridine are suspended in a mixture of 126 ml of acetone and 14 ml of water. The suspension is reacted with 0.7 ml of concentrated hydrochloric acid and boiled for two hours. Then 5.6 g (3.07*10-2 mole) of <strong>[10030-85-0]L-rhamnose-monohydrate</strong> are added. The reaction mixture is boiled under reflux for six hours and then stirred at room temperature for a night. The precipitate is filtered off, washed on the filter at first with 10 ml of ethylacetate, then with 10 ml of ether and finally it is dissolved in 20 ml of water. 140 ml of acetone are added to the solution. The precipitate is separated and reprecipitated twice in the described manner. The precipitate is now dissolved in 40 ml of warm water and then acetone is added (about 60 l) drop by drop until precipitation begins. This reprecipitation is repeated three times, too. The thus-obtained product consists of pure dirhamnoside. The amorphous solid substance is dissolved in 100 ml of water and the solution is lyophilized. Decomposition temperature: 250-254 C.; [alpha]D =+486.5; [alpha]578 =-52.2; [alpha]546 =-281.9 (water);
EXAMPLE 6 3,6-Di-(alpha-L-rhamnopyranosyl-amino)-acridine 2.46 g (10-2 mole) of 3,6-diamino-acridine-hydrochloride and 4.0 g (2.2*10-2 mole) of <strong>[10030-85-0]L-rhamnose-monohydrate</strong> are suspended in a mixture of 10 ml of water and 90 ml of ethanol. The reaction mixture is stirred intensively and heated to a temperature of 70 C. After the addition of 0.5 ml or concentrated hydrochloric acid the mixture is stirred at the given temperature for another 90 minutes, while shining, flocculent crystals separate. The mixture is left to stand at room temperature for 12 hours and then it is filtered. 3.6 g (71.8%) of product are obtained.
Figure 2C) Methyl alpha-L-rhamnopyranoside (ref. 78): To a solution of 5 g (27.4 mmol) of <strong>[10030-85-0]L-Rhamnose monohydrate</strong> in 50 mL of MeOH was added 5g of Dowex X8-200 ion exchange resin (H+). The reaction mixture was refluxed for 24h, cooled to room temperature, and filtered. The residue was purified by flash chromatography on silica gel (DCM/MeOH, 88/12) to give 4.4 g of known methyl alpha-L-rhamnopyranoside as a yellow syrup (90%) as the first eluding product, and 400 mg of methyl beta-L-rhamnopyranoside (8%) as the second eluding one.
(2S,3S,4S,5S)-1-(pyrrolidin-1-ylimino)hexane-2,3,4,5-tetrol[ No CAS ]
Yield
Reaction Conditions
Operation in experiment
80%
In methanol; for 2.5h;Reflux;
In a 100 ml flask, N-aminopyrrolidine (688 mg, 8 mmol) was dissolved in 15 ml of methanol. <strong>[10030-85-0]L-<strong>[10030-85-0]rhamnose monohydrate</strong></strong> (910 mg, 5 mmol) was added and the mixture was stirred at the methanol reflux. After 2.5 h of stirring the reaction was complete according to the TLC. Volatiles were removed under reduced pressure andthe residue was recrystallized in MTBE-ethanol 4:1 mixture. Process yielded white crystals (926 mg, 3.99 mmol,80%) which were dried further in vacuum.
(2S,3S,4S,5S)-1-(piperidin-1-ylimino)hexane-2,3,4,5-tetrol[ No CAS ]
Yield
Reaction Conditions
Operation in experiment
83%
In methanol; for 3.75h;Reflux;
In a 100 ml flask, N-aminopiperidine (800 mg, 8 mmol) was dissolved in 15 ml of methanol. <strong>[10030-85-0]L-<strong>[10030-85-0]rhamnose monohydrate</strong></strong> (910 mg, 5 mmol) was added and the mixture was stirred at the methanol reflux. After 3.75 h of stirring the reaction was complete according to the TLC. Volatiles were removed under reduced pressure andthe residue was recrystallized in MTBE-ethanol 3:1 mixture. Process yielded white crystals (1021 mg, 4.15mmol, 83%) which were dried further in vacuum.
(2S,3S,4S,5S)-1-(azepan-1-ylimino)hexane-2,3,4,5-tetrol[ No CAS ]
Yield
Reaction Conditions
Operation in experiment
74%
In methanol; for 3.25h;Reflux;
In a 100 ml flask, N-aminoazepane (912 mg, 8 mmol) was dissolved in 15 ml of methanol. <strong>[10030-85-0]L-<strong>[10030-85-0]rhamnose monohydrate</strong></strong> (910 mg, 5 mmol) was added and the mixture was stirred at the methanol reflux. After 3.25 h ofstirring the reaction was complete according to the TLC. Volatiles were removed under reduced pressure andthe residue was recrystallized in MTBE. Process yielded white crystals (961 mg, 3.70 mmol, 74%) which were dried further in vacuum.
Example B-1 2-hexyldecyl 6-deoxy-L-mannopyranoside (rhamnose sugar) A=<strong>[10030-85-0]L-rhamnose-monohydrate</strong>: 15 g, 82.3 mmol, 1 eq B=2-hexyl-1-decanol: 66.46 g, 274.13 mmol, 3.3 eq Acidic catalyst=PTSA: 1.47 g, 9.13 mmol, 0.11 eq, Reaction time: 17 hours at 80 C. At the end of the reaction, ethyl acetate and a saturated NaHCO3 solution are added to the reaction medium and the product is extracted, before being purified by means of silica gel chromatography. 15.44 g of a colorless gel obtained, yield 48%. Mass spectrometry: detection of expected product in quasi-molecular ion form [M+NH4+]+ (m/z=406)
2-octyldodecyl 6-deoxy-L-mannopyranoside[ No CAS ]
Yield
Reaction Conditions
Operation in experiment
10%
Example B-2 2-octyldodecyl 6-deoxy-L-mannopyranoside (rhamnose sugar) A=<strong>[10030-85-0]L-rhamnose-monohydrate</strong>: 15 g, 82.3 mmol, 1 eq B=2-octyl-1-dodecanol: 49.2 g, 164.68 mmol, 2 eq Acidic catalyst=PTSA: 1.42 g, 8.23 mmol, 0.1 eq, Reaction time: 6 hours. At the end of the reaction, purification by means of silica gel chromatography. 3.7 g of a colorless oil obtained, yield 10%. Mass spectrometry: detection of expected product in quasi-molecular ion form [M-H]- (m/z=443) and [M+Na]+ (m/z=467)
2-decyltetradecyl 6-deoxy-L-mannopyranoside[ No CAS ]
Yield
Reaction Conditions
Operation in experiment
6%
Example B-3 2-decyltetradecyl 6-deoxy-L-mannopyranoside (rhamnose sugar) A=<strong>[10030-85-0]L-rhamnose-monohydrate</strong>: 15 g, 82.3 mmol, 1 eq B=2-decyl-1-tetradecanol: 58.41 g, 164.7 mmol, 2 eq Acidic catalyst=PTSA: 1.42 g, 8.23 mmol, 0.1 eq, Reaction time: 6 hours at 80 C. At the end of the reaction, purification by means of silica gel chromatography. 2.6 g of a colorless oil obtained, yield 6%. Mass spectrometry: detection of expected product in quasi-molecular ion form [M-H]- (m/z=449) and [M+Na+H]+ (m/z=524)