Kaplan FL 1 Flashcards
(10 cards)
What does a low elution volume in gel filtration indicate
a larger solute as they cant penetrate porous beads and travel length of column FASTER
so lower elution volume must be the bigger molecule (dimer) as opposed to a monomer
do aromatic groups make a molecule more non polar and whats the consequence on solubility ? on coupling?
aromatic groups are more hydrophobic and less soluble in water
coupling is the combination of molecules
leads to slower coupling ( less joining) and aggregation of NP groups which impedes peptide synthesis
Why are aromatic rings non polar? and is it found in organic or aqeous layers?
aromatic rings have alternating pi electrons allowing for conjugation to occur throughout most of the molecule. Conjugation delocalizes E so the molecule is overal NP and is solunle in organic solvents
what is a phenol
benzene ring with alcohol attached
ether
ether has no carbonyl
what are the differences between alpha D glucose and Beta D glucose?
the hemiacetal carbons are opposite absolute confiugrations
they are anomers NOT enantiomers
both are reducing sugars, both take pyranose form with 6 sugars
What causes formation of water globules?
hydrogen bonding
which has higher boiling point: proponol or proponal?
high bp has to do with hiproponal is an aldehyde and they cannot hydrogen bond
proponol is a ketone with a hydroxy group and is can only have weak dipole interactions
purpose of a protecting group
reversibly react with a functional group to prevent undesired side chain reactions of that functional group by deprotection later
via
- reducing nucleophilicity of amino group
- increasing yield of product (by preventing side reactions)
- decreasing levels of impurity (decrease impurities and protect)
how is a cyclic ester made?
condensation of alcohol group and a carboxylic acid in the same molecule
