To determine the correct sequence of intermediates in the biosynthesis of opium alkaloids, we must understand the biosynthetic pathway. Here's how the pathway unfolds:
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Tyrosine (A): This is the starting point in the biosynthesis of opium alkaloids. Tyrosine, an amino acid, is first converted into norcoclaurine through enzymatic reactions.
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Reticuline (B): Following norcoclaurine, various modifications lead to the formation of reticuline, an important intermediate.
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Morphine (D): Through a series of steps involving methylations, dehydrogenations, and other transformations, reticuline is converted into morphine.
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Thebaine (E): Morphine can be further converted into thebaine. Thebaine is another alkaloid which serves as a precursor for other opium alkaloids and is more potent structurally compared to morphine.
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Codeine (C): Finally, codeine, which is an alkaloid derived from morphine, is synthesized. It is less potent than morphine but is a crucial opium alkaloid.
Thus, based on the biosynthetic sequence described, the correct order is A, B, D, E, C. Therefore, the correct answer is the option: A, B, D, E, C.