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Chapter 34: Problem 767

Ecdysone is the molting hormone (not a pheromone) that encourages the maturation of a larval stage of the silkworm into the pupal stage. It can kill insects by causing premature molting. (a) What general class of compounds is respresented by ecdysone? (b) Identify the chiral centers and assign their absolute configurations where possible. (c) How many products would be produced if ecdysone were reduced by catalytic hydrogenation under conditions that resulted in the uptake of two equivalents of hydrogen? (d) What, if anything, would be the relationship among these compounds?

Short Answer

Expert verified
(a) Ecdysone belongs to the general class of compounds called steroid hormones. (b) Without knowing the specific structure of ecdysone, we cannot identify chiral centers and their absolute configurations. (c) The number of products produced by catalytic hydrogenation depends on the double bonds present in the structure. Since the ecdysone structure is not given, we can't calculate the exact number of products produced. (d) The compounds obtained from the hydrogenation of ecdysone would be diastereomers of each other, as they have different configurations at some but not all chiral centers.

Step by step solution

01

Part (a): Identify the general class of compounds represented by ecdysone

Ecdysone is a steroid hormone that plays a crucial role in the development and metamorphosis of insects. The general class of compounds represented by ecdysone is the steroid hormones. These hormones have a specific structure composed of four cycloalkane rings (three cyclohexane rings and one cyclopentane ring) that are fused together.
02

Part (b): Identify the chiral centers and assign their absolute configurations

To identify the chiral centers in ecdysone, first, we need to recognize the carbon atoms that have four different groups attached to them. Chiral centers are depicted with an asterisk (*) in the structure. Once we identify all the chiral centers, we can use the Cahn-Ingold-Prelog (CIP) system to determine the absolute configuration (R/S) of each carbon. Unfortunately, without knowing the specific structure of ecdysone in this exercise, we cannot identify the chiral centers and determine the absolute configuration of them. In a practical situation, you would be provided with the structure or be able to look it up.
03

Part (c): Determine the number of products produced by catalytic hydrogenation

If ecdysone is reduced by catalytic hydrogenation under conditions that resulted in the uptake of two hydrogen equivalents, the number of products produced would depend on the reduction of the double bonds present in the structure. Since the ecdysone structure is not given, we can't calculate the exact number of products produced. However, the general approach would be to evaluate the double bond positions and analyze their reduction to single bonds. Each double bond reduced could lead to one or more stereoisomers, depending on the number of chiral centers affected.
04

Part (d): Analyze the relationship among the obtained compounds

The relationship among the compounds obtained from the hydrogenation of ecdysone would be that they are diastereomers of each other. This is because the hydrogenation process changes the configuration of carbon atoms involved in the double bonds but does not affect the other chiral centers in the molecule. Diastereomers are a type of stereoisomers that are not mirror images of each other.

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Most popular questions from this chapter

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