WANTED: Ergosterol biosynthesis precursors

[Joerg Mueller]

For investigations of potential new antimycotics I'm desperately looking
for

- Episterol (ergosta-7,24-dien-3-ol)
- Fecosterol (ergosta-8,24-dien-3-ol)
- Zymosterol (cholesta-8,24-dien-3-ol)
- 4,4-dimethylcholesta-8,14,24-trienol
- 4,4-dimethylzymosterol
- Ignosterol (4,4-dimethylcholesta-8,14-dienol)

I would need approx. 100mg of each substance as reference standards for
a MS database.
Who knows where I can obtain these substances (e.g.  research groups,
custom synthesis,....)???
Thanks a lot!