20 - CARBOHYDRATES AND NUCLEIC ACIDS Flashcards
what is that Barton McCombie Reaction
deoxygenation
replace the C-O bond by a C-H bond
synthesis of (+) Aberrarone A
what is the mechanism of the Barton McCombie Reaction
what are some other o-thiocarbonyl derivates that undergo the Barton McCombie reaction
how is glucose deoxygenated at C3
mechanism of deoxygenation of glucose at C3
how does deoxygenation happen naturally
happens by ribonucleotide reductase
make DNA from RNA
RR is hyperactive in cancer cells, because they have the pressure to make more DNA to divide more
this could be a target for potential cancer treatment
vitamin C function
vitamin C is made from D-glucose in plants
humans do not have the enzymes to make vitamin C so we must obtain i from the diet
vitamin C is antioxidant: slows down the oxidation of other molecules
converts OH radicals to water made
how is vitamin C made from D-glucose
why is the C3 OH on vitamin C more acidic than the C2 OH group?
more possible resonance structures
due to the fact that vitamin C is a vinylogous acid (a double bond separates the C=O and the acidic OH group on C3
more acidic than just a normal COOH
this drops the pKa down to 4.17
chitin structure and characteristics
carbohydrates on cell surfaces
what are N and O glycoproteins linked to?
N: linked to asparagine
O: linked to serine/threonine
SARS-CoV-2 and sugars
blood type and sugars
how did Alexander R. Todd analyse the structure of DNA and RNA
through hydrolysis
how to determine whether the sugar was furanose or pyranose
what are the forms of the bases and what is the most stable form?
keto and enol
keto is the true form
structure of DNA proposed by pauling and why it was wrong
