Functional groups oxidation level

Krikorian, S.E. 1988. Methodology for quantifying functional group oxidation state levels and for analyzing organic reactions for oxidation-reduction behavior. Am. J. Pharm. Educ. 52, 177-180. 

Scheme 3)10. Indeed, independent photolysis of 2,4-cyclohexadien-l-ones 12 and 13 afforded the macrolides 15. These reactions likely proceed via a common intermediate, in this case dienylketene 14, which is trapped intramolecularly by the pendant hydroxyl group. Adjustment of the oxidation level and functional group interconversion then led efficiently to the desired macrolide 17. The sulfonyl group was used for two reasons first, to easily transform lactones 15 into dienyl lactones 16 needed for 17, and secondly, to control the regiochemistry of the Wessely oxidation of phenolic precursor needed to produce the photolysis substrates 12 and 13. 

An ECD measures the current generated by electroactive analytes in the HPLC eluent between electrodes in the flow cell. It offers sensitive detection (pg levels) of catecholamines, neurotransmitters, sugars, glycoproteins, and compounds containing phenolic, hydroxyl, amino, diazo, or nitro functional groups. The detector can be the amperometric, pulsed-amperometric, or coulometric type, with the electrodes made from vitreous or glassy carbon, silver, gold, or platinum, operated in the oxidative or reductive mode. Manufacturers include BSA, ESA, and Shimadzu. 

Notwithstanding what has been stated above (generalisation 2), the construction of the molecular framework has priority over the oxidation levels of the functional groups and even of the carbon skeleton itself. This means that all the following compounds are synthetically equivalent ... 

Bifunctional systems In the case of bifunctional systems (or molecules) only two alternatives are possible the bifunctional relationships are either "consonant" or "dissonant" (apart from molecules or systems with functional groups of type A to which we have referred to as "assonant"). In the first case, the synthetic problem will have been solved, in principle, in applying the "heuristic principle" HP-2 that is to say, the molecule will be disconnected according to a retro-Claisen, a retro-aldol or a retro-Mannich condensation, or a retro-Michael addition, proceeding if necessary by a prior adjustment of the heteroatom oxidation level (FGI). 

An overall strategy for the synthesis of 1,2,5-thiadiazoles from the acyclic N-C-C-N grouping and sulfur monochloride was proposed in 1967 (1967JOC2823). The N-C function could vary over oxidation levels of amine, imine, cyanide, oxime and nitroso derivatives. Aliphatic and aromatic compounds having these functionalities in many combinations reacted with sulfur monochloride to form appropriately substituted or fused 1,2,5-thiadiazoles. Based on this model, a large... 

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