importance of functional groups

• Amines


  Have many uses in Biology such as bioregulation, neurotransmission and defense against predators
• Because of their high degree of biological activity, many amines are used as drugs and medicines
• Alkaloids


  An important group of biologically active amines, synthesized mostly by plants as protection from being eaten by insects and other animals
• Acetylcholine


  A neurotransmitter that carries impulses to receptor cells, contains a quaternary ammonium group, is highly soluble in water and highly diffusible, released by the presynaptic membrane in the neuron in packets of about 104 molecules
• 1. Nitrosoamines are very powerful carcinogens which scientists fear may be present in many foods, especially in cooked meats that have been cured with sodium nitrite
• Formaldehyde


  A famous aldehyde that is a gas
• Formaldehyde


  • Makes formalin with the 40% solution in water
  • Used for preserving biological specimens
  • Used in the tanning, embalming, and preparing glues, and polymeric products such as insecticides, germicides, and fungicides for plants
  • Used in photography and drug testing
  • Reacts with phenol to form Bakelite used in coatings, adhesives, and plastics

  
• Acetaldehyde


  Used for the production of pyridine derivatives, and acetic acid

  
• Benzaldehyde


  • Used in cosmetic products, dyes, and perfumes
  • Added to food products to give almond flavor
  • Used as bee repellent

  
• Many aldehydes naturally occur as flavoring agents such as benzaldehyde, vanillin, and the oil of cinnamon
• Many aldehydes have various essential functions in the bodies of human beings and other living organisms
• Acetone


  • The most common ketone, an ideal solvent for many synthetic fibers and plastics
  • Used in households as paint thinner and nail polish remover
  • Used in medicine for acne treatment and chemical peeling
• Methyl ethyl ketone (butanone)


  • Commonly used solvent, used for production of plastics, varnishes, textiles, paraffin, wax, and paint remover
  • Used for welding of plastics due to its dissolving properties
• Cyclohexanone


  Primarily used for the production of nylon
• Ketones are produced on a massive scale as industrial solvents, pharmaceuticals, and polymer precursors
• Cyclohexanone and methylethylketone are commonly used in biochemistry

  
• Products of ketones are used in paints and perfumes, for stabilizing ingredients and to avoid degradation
• Pharmaceutical compounds


  • Tetracyclines
  • Aspirin
  • Praziquantel
  • Corticosteroids
• Lactones


  Cyclic esters

  
• Lactones are common amongst natural products
• 1. ascorbic acid (Vitamin C)


  Necessary in the human diet to avoid the connective tissue disease, known as scurvy
• In acid solutions, ascorbic acid is an equilibrium mixture of the cyclic and acyclic forms, but the cyclic form predominates
• Erythromycin


  Member of the macrolide (large ring lactones) group of antibiotics, isolated from Steptomyces erythraeus

  
• Erythromycin


  • Inhibits bacterial protein synthesis, arresting bacterial growth and development
  • Effective against a wide range of diseases, including Staphylococcus, Streptococcus, Chlamydia and Legionnaires disease
• β-lactams


  Cyclic amides, unusually reactive amides capable of acylating a variety of nucleophiles

  
• β-lactams


  • The considerable strain in the four membered ring appears to be the driving force behind the unusual reactivity
  • When a β-lactam acylates a nucleophile, the ring opens and the ring strain is relieved
• Classes of β-lactam antibiotics

  • Penicillins
  • Carbapenems

  
• Penicillins


  Have a β-lactam ring fused to an unsaturated six-membered ring, containing a sulphur atom (thiazolidene ring)

  
• Carbapenems


  Have a β-lactam ring fused to an unsaturated five-membered with a sulphur atom bonded to the ring

  
• Antibiotics


  • Penicillin V
  • Cephalexin
  • Imipenem

  
• β-lactam antibiotics


  • Apparently work by interfering with the synthesis of bacterial cell walls
  • The carbonyl group of the β-lactam acylates an amino group on one of the enzymes involved in making the cell wall
  • The acylated enzyme is inactive for synthesis of the cell wall protein
• Drugs


  • Aspirin
  • Tylenol
  • Paracetamol