Some interesting occurrences of aldehydes and ketones in natural products
Some Interesting Occurrences of Aldehydesand Ketones in Natural ProductsOrganic Chemistry 212Minh Anh Nguyenminhanhnguyen@q.com
• Some naturally occurring aldehydes and ketones areimportant in living systems. Some function as sex hormones;others are used as flavorings and tasting. For example,testosterone, the male sex hormone, and progesterone, ahormone secreted by the ovaries that stimulates the growth ofcells in the uterine wall, both contain a ketone functionalgroup. In addition, aldehydes and ketones can be found infoods, fragrance chemicals, and medicines. Some aldehydes areresponsible for very pleasant tastes and odors, such as vanillinfrom vanilla beans, benzaldehyde from almonds,cinnamaldehyde from cinnamon, etc. Formaldehyde is used topreserve tissue. Acetaldehyde causes the unpleasant“hangover” feeling that can result from consuming alcoholicbeverages. Ketones are also responsible for many well-knownodors such as those of garlic and camphor. Muscone or muskoil is an ingredient in perfumes. The drug cortisone is a ketoneused to relieve individuals with rheumatism. Other uses forketones include industrial solvents such as acetone, which arealso used in every-day things like nail polish remover. In thehuman body, the scent of acetone in saliva or urine can warnof uncontrolled diabetes
Structures of Aldehydes and Ketones• Both aldehydes and ketones contain a carbonylgroup. The carbonyl is a very polar group.• Aldehydes have at least one H attached. Ketoneshave two R’s attached to the carbonyl group.AldehydesR HOKetoneR ROsp2CarbonylgrouppentanalOO2-pentanone
The differences between aldehydes andketones• Aldehydes are less steric hindered than ketones.• Aldehydes have fewer electron donating groups (EDGs)which can stabilize an electron-poor area• Aldehydes are readily oxidized to carboxylic acids, andketones resist oxidation. The oxidation of a primaryalcohol produces an aldehyde, and the oxidation of asecondary alcohol yields a ketone.
Physical Properties of Aldehydes andKetones• Aldehydes and Ketones have higher boiling pointsthan hydrocarbons, but have lower boiling pointsthan alcohols, because they have no H attached tothe O.• Aldehydes and Ketones have strong odors, and areoften used as flavorings or scents.• Small aldehydes are reasonably soluble in water.Large aldehydes are less polar and dissolve morereadily in nonpolar organic solvents.
Aldehydes can be found in food• Flavoring and or scent made from Aldehydes
Aldehydes can be found in foodOctanal is found both in orange oiland orange juice. Its usedindustrially to supply an orange,especially to perfumes andfood preparations.
Aldehyde can be found in Human Bodyand Fragrance ChemicalRetinal (retinaldehyde) is one of the many forms of vitamin Aand the chemical basis of Human and animal vision. It allowscertain microorganisms to convert light into metabolic energy.
Aldehydes can be found in medicine• Formaldehyde is also an extremelytoxic substance; it has an irritating odor.• Formaldehyde denatures proteins, renderingthem insoluble in water and resistant tobacterial decay. It is used to preserve tissue.• Acetaldehyde isproduced when one’s livermetabolizes ethanol(drinking alcohol) and causesthe symptoms of a hangover.
Ketones can be found in human body• Testosterone is the male sex hormone. Progesterone isthe hormone produced by the female ovary afterovulation.• Aldosterone is secreted when blood sodium ion levels aretoo low to cause the kidney to retain sodium ions. Ifsodium levels are elevated, aldosterone is not secreted,so that some sodium will be lost in the urine. Aldosteronealso controls swelling in the tissues.
Ketones can be found in Insects• Pheromones are chemicals released by an organism into its environmentenabling it to communicate with other members of its own species. They arereleased by both insects and mammals in many situations such as finding foodand mates, aggregating to take advantage of food resources, protecting sites ofovipositor, and escaping predation, etc.structure of the western pine beetle pheromone
Ketones can be found in one’s health• In human bodies, Ketones are transported from the liver to othertissues.• Ketones are chemicals which appearin the blood and urine when body fat isbeing broken down for energy. Ketonesare formed when not enough food hasbeen eaten to provide the energy thebody needs.• The concentration of ketones is lessthan 1 mg/100 mL of blood. If theketones concentration rises to higherlevels, it is a warning of uncontrolleddiabetes. It is easy to detect in theurine and odor can be noted onthe breath.