Synthesis of Echinosporin

C10H9NO5
Principal investigator | Amos B. Smith, III |
---|---|
Publication year | 1989 |
Synthesis type | Partial |
Number of steps | 16 (linear) |
References |
Part 1 of 1
SM obtained in 3 steps from ascorbic acid. See J. Org. Chem. 1985, 50, 3462

3,4-Dihydropyran,
Pyr.TsOH
CH2Cl2
RT, 12 h, 100%

i-Bu2AlH
CH2Cl2
-78 °C, 1 h, 100%

Pyr.TsOH
MeOH
RT, 3 h

H2SO4
Acetone
0 °C to RT, 2 h, 53% (2 steps)



2-Cyclopentenone
hv
Pentane
RT, 22 h, 50%
"Also isolated were other regio and stereoisomers (29%)"

- i-Pr2NLi
- PhNTf2
THF
-78 to -20 °C, 24 h, 76%

Et3N,
Pd(OAc)2,
Ph3P,
CO
DMF, MeOH
RT, 20 h, 83%

- TMS2NK
- (+)-(Camphorsulfonyl)oxaziridine
HMPA, PhMe, THF
-78 °C, 2 h, 90 %
See the Davis Asymmetric Hydroxylation

Bio-Rad AG50W-X2 resin
H2O, MeCN
RT, 3 d, 69%

Pd2(dba)3,
Diallyl carbonate
CHCl3, MeCN
80 °C, 3 h, 54%

NH3
H2O, MeOH
RT, 20 h, 86%


HCl
H2O
RT, 48 h, 100%

