Heterocycles Nomenclature 12292021 1 Oxygen Containing Heterocycles 3

Heterocycles ü Nomenclature 12/29/2021 1

Oxygen Containing Heterocycles ü 3 -Membered Ring : : Ethylene Oxide or oxirane ü Oxirane formation in our body 12/29/2021 2

Oxygen Containing Heterocycles ü Examples of epoxides in our system Squalene Epoxide 12/29/2021 3

Oxygen Containing Heterocycles ü Reactions of Epoxides Acid Opening of Epoxides 12/29/2021 4

Oxygen Containing Heterocycles ü Reactions of Epoxides Enzymatic Opening of Epoxides 12/29/2021 5

Oxygen Containing Heterocycles ü Reactions of Epoxides Opening of Epoxides with Amines and Alcohols 12/29/2021 6

Oxygen Containing Heterocycles ü Higher Oxides Oxetane 12/29/2021 oxolane oxane 1, 4 -dioxane 7

Oxygen Containing Heterocycles ü Higher Oxides Stability of these oxides change drastically on a-substitution Lactones Hemi-acetals 12/29/2021 anhydrides acetals 8

Oxygen Containing Heterocycles ü Examples of Acetals or Hemi-Acetals in Nature 12/29/2021 9

Oxygen Containing Heterocycles ü Interconversion of a- and b-forms of sugars The phenomenon of mutarotation 12/29/2021 10

Oxygen Containing Heterocycles ü Examples of sugars in natural systems Deoxynucleic Acids and Ribonucleic Acids Live link: http: //www. bmrb. wisc. edu/referenc/nomenclature/ 12/29/2021 11

Oxygen Containing Heterocycles ü Sugars and Diabetes Glycated Hemoglobin (Hb. A 1 c or GHb) Also called glycosylated hemoglobin. The saccharide equilibrium is the reason for the formation of glycated hemoglobin in diabetic patients. Excess free plasma sugar, and therefore the open-chain aldehyde, reacts with the N-terminal NH 2 group of hemoglobin (or lysine side chains) to form glycated adducts, which are detected to confirm and monitor diabetes. The upper limit for a normal individual is 7% Hb. A 1 c. 12/29/2021 12

Oxygen Containing Heterocycles ü Fructose ü Sucrose 12/29/2021 13

Oxygen Containing Heterocycles ü Polysaccharides – Cellulose and Starch 12/29/2021 14