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Beta-lactam antibiotics like Amoxicillin, DO NOT reduce the…

Beta-lactam antibiotics like Amoxicillin, DO NOT reduce the efficacy of estrogenic birth control pills, but the bright red, antibiotic, known as Rifampicin, does.  Consider the representations of Rifampicin below and answer the following:       i) These figures were obtained from Wikipedia and to be honest, the line angle representation is terrible.  Using the 3D stick drawing as a guide, determine the configuration of the alkene that is indicated by the black arrow. [conf]       ii) The N-methylpiperazine ring was synthesized earlier in the semester when we tackled the SOD for the antihistamine known as Zyrtec.  If the entire ring group was removed from the imine nitrogen and replaced with H, this would now make the imine [moreless] (ignore steric effects).       iii) What is the configuration of the ketal carbon? [RS]       iv) Although Rifampicin is not a beta-lactam antibiotic it does possess a lactam unit?[tf]   v) Rifampicin contains a steroidal skeleton. [tf2]     vi) Complete acid hydrolysis would release the colored, aromatic core.  How many acyl groups would be present in this aromatic core after complete hydrolysis? [core]

Here kitty kitty.  The scheme below from a C&EN article in D…

Here kitty kitty.  The scheme below from a C&EN article in December 2018 shows a potential biosynthetic pathway for one of the active components in catnip. A) Acyl Addition D) Claisen G) Diels-Alder J) Hydrolysis M) Reduction B) Acyl Substitution E) Dehydration H) Fischer K) Michael N) Robinson C) Aldol F) Dieckmann I) Hydration L) Oxidation O) Sandmeyer   Choose the letter that best corresponds to what is occurring during this multi-step mechanism. NO LETTER SHOULD BE USED MORE THAN ONCE. i) What letter best describes the process that is occurring during step 1? [step1] (enter letter only)   ii) The enol intermediate undergoes a two step process to generate the corresponding lactol (hemiacetal) structure.  Enter the letters that correspond to step 2 and step 3. Step 2: [step2] (enter letter only) Step 3: [step3] (enter letter only)   iii) What letter best describes the process that is occurring during the last arrowed step to produce the lactone? [step4] (enter letter only)