반응 #1140132

반응 방정식

NaOH

isopropyl alcohol

cholesteryl tosylate

4-hydroxybutanenitrile

hydrochloric acid

→

4-(Cholest-5-en-3β-yloxy)butanoic acid

formula IX

cholest-5-en-3β-yloxyacetic acid

용매

diethyl ether

toluene

반응 조건

후처리

1. 1
   기타the solvent was evaporated in vacuo
2. 2
   기타The obtained crude 4-(cholest-5-en-3β-yloxy)butanenitrile
3. 3
   온도The mixture was cooled to room temperature
4. 4
   건조The combined extracts were dried over anhydrous MgSO4
5. 5
   농축concentrated in vacuo

실험 절차

A solution of cholesteryl tosylate (2.8 g, 5.1 mmol) and 4-hydroxybutanenitrile (0.61 g, 7.1 mmol) in toluene was stirred at 120° C. for 24 h and then the solvent was evaporated in vacuo. The obtained crude 4-(cholest-5-en-3β-yloxy)butanenitrile was dissolved in isopropyl alcohol (30 ml), aqueous NaOH (12%; 100 ml) was added and the mixture was stirred at 100° C. for 3 days. The mixture was cooled to room temperature, aqueous hydrochloric acid (10%, 100 ml) was added and the product was taken in diethyl ether (4×30 ml). The combined extracts were dried over anhydrous MgSO4 and concentrated in vacuo. Flash chromatography of the residue on silica gel column (320 ml) in toluene-ethyl acetate (gradient: 0-40% ethyl acetate, 10 ml/min, 160 min) afforded 4-(Cholest-5-en-3β-yloxy)butanoic acid (general formula IX, where n2=3; 345 mg, 10%). 1H NMR (400 MHz, CHCl3) δ (ppm): 5.32-5.39 m, 1H (H-6); 3.55 td, J=5.90, 1.40 Hz, 2H (CH2-1′); 3.17 tt, J=11.21, 4.39 Hz, 1H (H-3); 2.49 t, J=7.01 Hz, 2H (CH2-3′); 2.36 ddd, J=13.17, 4.71, 2.08 Hz, 1H (H-4a); 2.14-2.24 m, 1H (H-4b); 1.93-2.05 m, 2H (CH2-1, H-12); 1.90 t, J=6.20 Hz, 2H (CH2-2′); 1.78-1.88 m, 3H (H-2, H-7, H-16); 1.02-1.63 m, 22H (cholesterol); 1.01 s, 3H (CH3-19); 0.92 d, J=6.57 Hz, 3H (CH3-21); 0.88 d, J=1.77 Hz, 3H (CH3-26); 0.86 d, J=1.77 Hz, 3H (CH3-27); 0.68 s, 3H (CH3-18); 13C NMR (101 MHz, CHCl3) δ (ppm): 178.28 (C-1′) 140.76 (C-5) 121.69 (C-6) 79.31 (C-3) 66.88 (C-4′) 56.77 (C-14) 56.16 (C-17) 50.18 (C-9) 42.31 (C-13) 39.78 (C-12) 39.51 (C-24) 38.98 (C-4) 37.18 (C−1) 36.86 (C-10) 36.18 (C-22) 35.78 (C-20) 31.94 (C-7) 31.88 (C-8) 31.37 (C-2′) 28.29 (C-2) 28.23 (C-16) 28.01 (C-25) 25.06 (C-3′) 24.28 (C-15) 23.83 (C-23) 22.81 (C-26) 22.55 (C-27) 21.06 (C-11) 19.36 (C-19) 18.71 (C-21) 11.86 (C-18); for C31H52O3 monoisotopic mass: calculated: 472.4. found: MS ESI m/z: 495.4 [M+Na]+. for C31H52O3 calculated: 78.76% C; 11.09% H. found: 78.80% C; 11.18% H; IR (CHCl3): 3517, 2718, 1741, 1710, 1415, 1285 (COOH); 1134, 1105, 1070, 1083, 841 (ether); 1670, 1334 (C═C); 2954, 2869, 1445, 1366 (Me); [α]D-27.2° (c 0.136; CHCl3).

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