November 25, 2024, 05:26:14 AM
Forum Rules: Read This Before Posting


Topic: Question on degradation  (Read 2600 times)

0 Members and 1 Guest are viewing this topic.

Offline mycotheologist

  • Regular Member
  • ***
  • Posts: 46
  • Mole Snacks: +1/-0
Question on degradation
« on: March 25, 2012, 12:31:52 AM »
Heres the question:

all I can think of is maybe the drug undergoes a transesterification with the ethanol yielding a methyl ester instead of a isopropyl ester. If thats the answer, I'd have no idea how to prevent it other than replacing the ethanol with something else.

Offline discodermolide

  • Chemist
  • Sr. Member
  • *
  • Posts: 5038
  • Mole Snacks: +405/-70
  • Gender: Male
    • My research history
Re: Question on degradation
« Reply #1 on: March 25, 2012, 03:22:28 AM »
Heres the question:

all I can think of is maybe the drug undergoes a transesterification with the ethanol yielding a methyl ester instead of a isopropyl ester. If thats the answer, I'd have no idea how to prevent it other than replacing the ethanol with something else.

You mean the ethyl ester!
Instead of ethanol use isopropanol for the liquid phase!
Development Chemists do it on Scale, Research Chemists just do it!
My Research History

Offline AWK

  • Retired Staff
  • Sr. Member
  • *
  • Posts: 7976
  • Mole Snacks: +555/-93
  • Gender: Male
Re: Question on degradation
« Reply #2 on: March 25, 2012, 03:51:07 AM »
Isopropanol is quite safe (nontoxic). Also check pH since isopropyl esters easy undergo acidic hydrolysis (ethanol usually contains at least a few percent of water).
AWK

Offline mycotheologist

  • Regular Member
  • ***
  • Posts: 46
  • Mole Snacks: +1/-0
Re: Question on degradation
« Reply #3 on: March 25, 2012, 11:05:09 AM »
You mean the ethyl ester!
Instead of ethanol use isopropanol for the liquid phase!

Yeah ethyl ester, sorry. It would be pretty insane to use methanol as a solvent in a lotion lol. Ah yeah, I didn't think of isopropanol. Its used as a topical antiseptic so obviously it won't exhibit any toxicity when used as a lotion solvent. This answer seems too simple for the question though. Is transesterification the only probable degradant of this compound, assuming that the excipients (besides the ethanol) are inert?

Sponsored Links