Dry MeOH) in MeOH (1 mL), was added AcOH (0.3 mL) as well as a
Dry MeOH) in MeOH (1 mL), was added AcOH (0.3 mL) and also a resolution of 9 (64.0 mg, 0.1 mmol) in MeOH (1 mL). The resolution was degassed and stirred below a slightly optimistic pressure of hydrogen (balloon) at 23 for 16 h. The reaction was then filtered by means of a quick pad of Celite, and washed with CH2Cl2. The mixture was concentrated in vacuo and the HSP40 list residue was redissolved in CH2Cl2 and was neutralized by anhydrous Na2CO3. The solvent was removed by vacuum as well as the crude item was subjected to benzyl protection without the need of additional purification. Beneath Ar atmosphere, to a remedy of the hydrogenated crude item (0.15 mmol) in anhydrous THF was added NaH (4.8 mg, 0.four mmol). Soon after stirring for five min, BnBr (19 mL, 0.15 mmol) and nBu4NI (11.1 mg, 0.03 mmol) was added along with the mixture was stirred at 23 for 16 h. The reaction was quenched by 1M KHSO4. The aqueous remedy was extracted with EtOAc (3 times). The combined organic layers have been dried with MgSO4, and concentrated in vacuo. IP Compound Purification with the residue by flash chromatography on silica gel, eluting with 1.0 2.5 MeOHCH2Cl2 gave the preferred product as a white foamy solid.(2S,3S)-1-(Benzyloxy)-4-((tert-butyldiphenylsilyl)oxy)-3-methylbutan-2-amine (syn-13) The compound was ready based on the standard hydrogenolysis and benzylation procedure. Purification by flash chromatography afforded syn-13 as a white foamy strong (22.two mg, 50 yield in two measures). 1H NMR (400 MHz, CDCl3) 7.71 7.65 (m, 4H), 7.48 7.28 (m, 11H), four.55 (d, J = four.eight Hz, 2H), three.77 3.60 (m, 3H), three.47 (dd, J = 9.3, 7.6 Hz, 1H), 3.18 (td, J = 7.2, three.four Hz, 1H), 2.80 (br, 2H), 1.90 1.79 (m, 1H), 1.08 (s, 9H), 0.94 (d, J = 7.0 Hz, 3H); 13C NMR (100 MHz, CDCl3) 138.1, 135.6, 133.four, 133.three, 129.7, 128.4, 127.8, 127.7, 73.3, 72.8, 66.8, 53.9, 38.1, 27.0, 19.two, 13.9.J Org Chem. Author manuscript; obtainable in PMC 2014 December 06.Khumsubdee et al.PageNIH-PA Author Manuscript NIH-PA Author Manuscript NIH-PA Author Manuscript(2R,3S)-1-(Benzyloxy)-4-((tert-butyldiphenylsilyl)oxy)-3-methylbutan-2-amine (anti-13) The compound was prepared as outlined by the standard hydrogenolysis and benzylation process. Purification by flash chromatography afforded anti-13 as a white foamy solid (22.three mg, 50 yield in two measures). 1H NMR (400 MHz, CDCl3) 7.70 7.67 (m, 4H), 7.49 7.28 (m, 11H), four.54 (s, 2H), 3.68 three.58 (m, 2H), three.56 three.49 (m, 1H), three.38 (dd, J = 10.two, 6.five Hz, 1H), 3.26 (br, 1H), 1.83 (br, 1H), 1.51 (br, 2H), 1.08 (s, 9H), 0.92 (d, J = 6.9 Hz, 3H); 13C NMR (100 MHz, CDCl3) 138.five, 135.6, 133.8, 133.7, 129.six, 128.4, 127.7, 127.6, 74.3, 73.2, 66.eight, 29.7, 26.9, 19.three, 11.7. Relative stereochemistry determination of 9: the 13C NMR data of syn-13 matched with reported data39 and differ from that of anti-13. As a result, the relative stereochemistry assignment was confirmed.Standard Process for the Preparation of -Amino AcidTo Raney ickel ( 1.five g, prewashed with dry MeOH) in MeOH (ten mL), was added AcOH (three mL) and also a answer of 9 (1.44 g, 2.25 mmol) in MeOH (10 mL). The option was degassed and stirred under a slightly positive stress of hydrogen (balloon) at 23 for 16 h. The reaction was then filtered through a brief pad of Celite, and washed with CH2Cl2. The mixture was concentrated in vacuo along with the residue was redissolved in CH2Cl2 and was neutralized by anhydrous Na2CO3. The solvent was removed by vacuum as well as the crude solution was subjected to Fmoc-protection without the need of further purification. To a remedy on the above crude produc.
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