Some microorganisms have evolved cellular machinery that carries out chemical transformations in a manner analogous to that of the pyruvate dehydrogenase complex (PDC). One example of these remarkable transformations is shown below. معلم H3C 1. TPP 2. lipoamide CH3 + 3. Coenzyme A H3C H H3C SCOA он Provide a complete curved-arrow mechanism for all three steps of this multistep enzymatic transformation. You may abbreviate the structure of Coenzyme A as "COA-SH" in your mechanism. You do not have to show a mechanism for the regeneration of the lipoamide cofactor.

Fill in the missing products and intermediates

For the following reaction, draw all of the synthetic intermediates that are formed in each step, including the final product.

6. For the following reaction, draw all of the synthetic intermediates that are formed in each step, including the final product. 1. H2SO4 2. mCPBA 3. MgBr-CH2CH3 4. H20 HO.

OCH3 + CH3NH2 a. Draw the structure of the tetrahedral intermediate INITIALLY-FORMED in the reaction shown. • • • You do not have to consider stereochemistry. Do not include counter-ions, e.g., Na+, I, in your answer. In cases where there is more than one answer, just draw one. √n [ ? ChemDoodle b. Draw the structures of the organic products of the acyl transfer reaction. • You do not have to consider stereochemistry. • Draw the neutral form of the products: no charges.

Select the correct IUPAC name for the following organic substrate, including the R or S designation where appropriate, and draw the major organic product(s) for the SN1 reaction. Include wedge-and-dash bonds and draw hydrogen on a stereocenter. Br HBr HO. Br

For the following reaction, draw all of the synthetic intermediates that are formed in each step, including the final product.