Open-Chain Analogues of Neplanocin A
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0.91 (s, 9H), 0.08 (s, 6H); 13C NMR (CDCl3)δ 154.93, 152.48, 147.93, 144.85,
139.57, 130.67, 129.26, 117.10, 75.40, 48.94, 20.76, 14.89, 12.80, −6.32.
1-[(E )-4-(t-Butyldimethylsilyloxy)-3-phenyl-but-2-enyl]-4-amino-6-[(4-
1
chlorophenyl)sulfan yl]-9H-purine (18).
Yield 21%; H NMR (CDCl3,
300 MHz) δ 8.78 (br s, 1H), 7.56–7.44 (m, 5H), 7.41 (d, J = 7.2 Hz, 2H),
7.38 (d, J = 7.2 Hz, 2H), 5.53 (t, J = 7.3 Hz, 1H), 4.43 (d, J = 7.3 Hz, 2H),
4.08 (s, 2H), 0.92 (s, 9H), 0.07 (s, 6H); 13C NMR (CDCl3) δ 160.62, 150.48,
148.13, 142.93, 115.47, 67.10, 45.16, 25.90, 18.40, 13.74, −5.32.
1-[3,3ꢁ-Bis-(Hydroxymethyl)-prop-2-enyl]adenine (Ia).
To a solution of
compound 10 (250 mg, 0.54 mmol) in THF (5 mL), TBAF (3.23 mL, 1.0 M
solution in THF) at 0◦C was added. The mixture was stirred at room temper-
ature for 4 h and concentrated. The residue was purified by silica gel column
chromatography (MeOH/CH2Cl2, 1:2) to give compound Ia (46 mg, 36%)
as a white solid: mp 207–213◦C;UV (H2O) λmax 261.0 nm; 1H NMR (DMSO-
d6, 300 MHz) δ 8.12 (s, 1H), 7.20 (s, 1H), 5.61 (t, J = 7.32 Hz, 1H), 4.87
(d, J = 7.4 Hz, 2H), 4.13 (d, J = 5.48 Hz, 2H), 3.95 (d, J = 5.49 Hz, 2H);
13C NMR (DMSO-d6)δ 154.49, 152.09, 147.92, 144.96, 140.99, 119.43, 63.26,
62.86, 57.25, 31.14; Anal calc for C10H13N5O2: C, 51.06; H, 5.57; N, 29.77.
Found: C, 51.11; H, 5.68; N, 29.92.
The synthesis of compounds Ib–If was carried out by the same procedure
as described for the preparation of Ia.
1-[(E )-4-(Hydroxy)-3-methyl-but-2-enyl]adenine (Ib).
Yield 25%; mp
1
178–183◦C; UV (H2O) λmax 259.0 nm; H NMR (DMSO-d6, 300 MHz) δ
8.13 (s, 1H), 7.18 (s, 1H), 5.66 (s, 1H), 4.80 (d, J = 6.0 Hz, 2H), 4.45 (s, 2H),
1.80 (s, 3H); 13C NMR (DMSO-d6)δ 170.52, 156.40, 152.93, 147.95, 140.85,
135.37, 122.36, 68.22, 21.06, 14.34; Anal calc for C10H13N5O: C, 54.78; H,
5.98; N, 31.94. Found: C, 54.87; H, 6.18; N, 32.03.
1-[(E )-4-(Hydroxy)-3-phenyl-but-2-enyl]adenine (Ic).
Yield 19%; mp
175–184◦C;UV (H2O) λmax 260.0 nm; 1H NMR (DMSO-d6, 300 MHz) δ 8.68
(s, 1H), 8.12 (s, 1H), 7.22 (m, 5H), 5.75 (t, J = 7.3 Hz, 1H), 4.40 (s, 2H),
4.20 (s, 2H) ; 13C NMR (DMSO-d6)δ 154.92, 152.08, 147.97, 144.80, 142.65,
134.90, 128.46, 127.77, 126.28, 113.59, 72.54, 48.82; Anal calc for C15H15N5O:
C, 64.04; H, 5.37; N, 24.90. Found: C, 63.89; H, 5.48; N, 25.10.
1-[3,3ꢁ-Bis-(Hydroxymethyl)-prop-2-enyl]-6-chloropurine (Id).
Yield
1
83%; mp 202–211◦C (dec); UV (H2O) λmax 262.0 nm; H NMR (D2O,
300 MHz) δ 8.56 (s, 1H), 8.44 (s, 1H), 5.78 (t, J = 7.15 Hz, 1H), 5.01 (d,
J = 7.12 Hz, 2H), 4.30 (s, 2H), 4.12 (s, 2H); 13C NMR (D2O) δ 154.92,
151.39, 149.71, 143.07, 128.45, 121.11, 63.15, 57.02, 41.57; Anal calc for