Biodegradation Predictive Worksheet Reasoning: Barban


1. What was the first thing you focused on to guide your development of a pathway(s)?
E1 The readily susceptible parts of the molecule to metabolism are the ester linkage (hydrolysis), C-C1 bond cleavage (hydrolysis), and hydration of the acetylenic function group to make a carbonyl carbon
E2 Ester Cleavage, because it should be easily done.
2 weak bonds--amide & ester.
E3 Answers to 1 and 2. (of check list) were positive.
E4 Look for common/rapid reaction --- Are moieties/features present? (=ester, amide, beta-oxidation, unsubstituted aromatic rings, etc)

2. How did you proceed after your initial focus point?
E1 After ester hydrolysis, either dechlorination or acetylenic hydration might occur. The carbonyl carbon would form adjacent to the carbon bearing a hydroxyl group to avoid generating an alpha-halo ketone (and to generate an alpha-keto acid, eventually).
E2 Dioxygenations will take care of the aromatic compound. Not sure how to attack the acetylene bond, but it must be eliminated somehow.
E3 Proceeded to question 8 and 8a, which were also positive.
E4 "Erosion" of molecule to "core" structure(aromatic rings, etc.).
How did I proceed after initial focus point? (see work sheet instruction)
bullet #1 Yes, #2 Yes, #3 No, #4 Yes, #5 No, and #6 Yes, (Natural selection)