Creatine is a naturally occurring compound that helps provide energy to cells in the body, especially muscle cells. Draw an S2 mechanism that shows how creatine is produced from guanidoacetate and SAM (see Problem 8.66). H2N- H2N NH2 NH2 Guanidoacetate Creatine (S)-Adenosylmethionine (SAM) is a cosubstrate that is involved in biological methyl group transfers. SAM is believed to be produced by an Sy2 type of reaction between methionine and ATP, as shown below. H,N H,N N: N N H3N. H3N CO2 ОН ОН ОН ОН Methionine ATP SAM (a) Draw the appropriate curved arrows for this reaction. (b) Suggest why the reaction takes place with S as the nucleophilic atom instead of one of the negatively charged O atoms on methionine. 0=P-

Determine whether each of the following sugars is reducing or non-reducing.

Identify the type of glycosidic bond for each of the following sugars. Choose from a-(1-2), a- (1-3), a-(1-4), a-(1-5), a-(1-6), B-(1-2), ß-(1-3), ß-(1-4), ẞ-(1-5), ß-(1-6), or a,ẞ- (1+2) CH₂OH 0 HO H H OH H H H OH O a-(1-6) glycosidic bond OB-(1-5) glycosidic bond OB-(1-6) glycosidic bond Oa-(1-5) glycosidic bond CH₂ HO H H OH H H 0 H HP OH

what is the drawn out electron pushing mechanism

Classify each of the following compounds as reducing or non-reducing sugars. Please be very clear in your explanation.

Draw the complete electron pushing mechanism for the following transformation.

The sugars can be classified as either aldoses or ketoses. Classify each structure with the correct name. НО НО H Н CHO —H -H -OH -OH CH₂OH НО НО Н CH₂OH c=0 H -н -OH CH₂OH НО НО н CHO ketose -H -Н OH CH₂OH Answer Bank aldose CHO H-C-OH CH₂OH НО Н CH₂OH c=0 -Н -OH CH₂OH " CH2OH O CH2OH

H-C -OH CH₂OPO₂²- 3-phosphoglycerate ATP ADP Arrow-pushing Instructions AC XT H-C-OH :O: CH₂OPO3²- =C² H-C-OH -O OPO3² Enz-SH 3 CH₂OPO3²- 1,3-bisphosphoglycerate ADP PO S-Enz H-C-OH CH₂OPO3²- One step in the gluconeogenesis pathway for the biosynthesis of glucose is the partial reduction of 3-phosphoglycerate to give glyceraldehyde 3-phosphate. The process occurs by phosphorylation with ATP to give 1,3-bisphosphoglycerate, reaction with a thiol group on the enzyme to give an enzyme-bound thioester, and reduction with NADH. Draw curved arrows to show the movement of electrons in this step of the reaction mechanism. [Enzyme-bound thioester] NADH/H* NAD*, Enz-SH H H-C-OH CH₂OPO3²- Glyceraldehyde 3-phosphate :Ö: H-C-OH CH₂OPO3²- ADP 29