Organic Chemistry Ch 10. Nitrogen and Phosphorus-Containing Compounds

Question 1

Alpha carbon amino acid

Answer 1

Attached to an amino group, a carboxyl group, a hydrogen atom, and an R group, chiral center except for glycine

Question 2

Stereochemistry amino acids

Answer 2

Alpha carbon chiral center for all but glycine which is achiral, all are L-amino acids, all have (S) stereochemistry except for cysteine which is (R)

Question 3

Amino acids and amphotericness

Answer 3

All amino acids are amphoteric, Can act as acids or bases, get acidic characteristics from carboxylic acid and basic characteristics from amino group, in neutral solution exist as zwitterions (dipolar ions)

Question 4

Nonpolar nonaromatic amino acids

Answer 4

Alanine, valine, leucine, isoleucine, glycine, proline, methionine, tend to be hydrophobic and reside on the interior of proteins

Question 5

Aromatic amino acids

Answer 5

Tryptophan, phenylalanine, tyrosine, nonpolar amino acids tend to be hydrophobic and reside on the interior of proteins

Question 6

Polar amino acids

Answer 6

Serine, threonine, asparagine, glutamine, and cysteine, Tend to be hydrophilic and reside on the surface of proteins, making hydrogen bonds with the aqueous environment

Question 7

Negatively charged amino acids

Answer 7

Contain carboxylic acid in their R groups and include aspartic acid and glutamic acid, Tend to be hydrophilic and reside on the surface of proteins, making hydrogen bonds with the aqueous environment

Question 8

Positively charged amino acids

Answer 8

Contain amines in their R groups and include arginine, lysine, and histidine, Tend to be hydrophilic and reside on the surface of proteins, making hydrogen bonds with the aqueous environment

Question 9

Polar and charged amino acids properties

Answer 9

Tend to be hydrophilic and reside on the surface of proteins, making hydrogen bonds with the aqueous environment

Question 10

Peptide bonds

Answer 10

Form by condensation reactions and can be cleaved hydrolytically, resonance of bond restrictions motion around the CN bond which takes on partial double bond character, strong acid or base needed to cleave peptide bond

Question 11

Polypeptides

Answer 11

Made up of multiple amino acids linked by peptide bonds

Question 12

Proteins

Answer 12

Large, folded, functional polypeptides

Question 13

Synthesis of amino acids in lab

Answer 13

Stecker synthesis or Gabriel synthesis

Question 14

Strecker synthesis

Answer 14

Generates an amino acid from an aldehyde, aldehyde mixed with ammonium chloride and potassium cyanide, the ammonia attacks the carbonyl carbon, generating an immune, the immune is then attacked by the cyanide, generating an aminonitrile, the aminonitrile is hydrolyzed by two equivalents of water, generating an amino acid

Question 15

Gabriel synthesis

Answer 15

Generates an amino acid from potassium phthalimide, diethyl bromomalonate and an alkyl halide, phthalimide attacks the diethyl bromomalonate generating a phthalimidomalonic ester, the phthalimidomalonic ester attacks an alkyl halide adding an alkyl group to the ester, the product is hydrolyzed creating phthalic acid (with two carbonyls) and converting the esters into carboxylic acids, one carboxylic acid of the resulting 1,3 dicarbonyl is removed by decarboxylation

Question 16

Phosphorous containing compounds

Answer 16

Inorganic phosphate (Pi), the backbone of DNA

Question 17

Inorganic phosphate

Answer 17

A buffered mixture of hydrogen phosphate (HPO4)2- and dihydrogen phosphate H2PO4-

Question 18

Phosphodiester bonds

Answer 18

Found is backbone of DNA, a pyrophosphate (PPi, P2O7-2) is released when forming bond where the pyrophosphate can then be hydrolyzed into two inorganic phosphates

Question 19

Phosphate bond properties

Answer 19

High energy because the large negative charges in adjacent phosphate groups and resonance stabilization of phosphates

Question 20

Organic phosphates

Answer 20

Carbon-containing compounds that also have phosphate groups, notable examples are nucleotide triphosphate and DNA

Question 21

Phosphoric acid

Answer 21

Three hydrogens, each with a unique pKa, this wide variety in pKa allows phosphoric acid to act as a buffer over a large range of pH values