100% satisfaction guarantee Immediately available after payment Both online and in PDF No strings attached
logo-home
Previously searched by you
Previously searched by you
logo
Summary Comprehensive final exam review: EVERYTHING you need to know from student who got 93% in Orgo 2223. Includes notes from all prep 101 sessions. CA$58.07   Add to cart
Quickly navigate to
Preview
  2.  
  3. University Of Western Ontario (UWO )
  4.  
  5. Medical Sciences
  6.  
  7. Chem 2223

Summary

Summary Comprehensive final exam review: EVERYTHING you need to know from student who got 93% in Orgo 2223. Includes notes from all prep 101 sessions.
 21 views  0 purchase

Comprehensive final exam review: EVERYTHING you need to know from student who got 93% in Orgo 2223. Includes notes from all prep 101 sessions.

Preview 4 out of 86  pages

Document information

  • August 12, 2023
  • 86
  • 2023/2024
  • Summary

Subjects

Written for

All documents for this subject (1)

Seller

avatar-seller
oawn18

Content preview

CHEM 2223 FINAL EXAM
REVIEW
2pm April 22nd, 2023

,Carbohydrates
Monosaccharides
 Glycoprotein: proteins + short, branched carbs
o Cell-surface receptors
 Proteoglycan: proteins + long, linear carbs
o Connective tissue
 Peptidoglycan: short oligopeptides cross-linking long, linear carbs
o Cell walls of bacteria
 Lipopolysaccharides: fatty acids + carbs
o Outer membrane of gram-negative bacteria
 Empirical formula: CH2O
 Molecular formula: Cn(H2O)n
 Aldose = aldehyde
o Anomeric C connected to 1H
 Ketose = ketone
o Anomeric C not connected to an H (2C, 1OH, 1O)
 “ulose” = ketone
 Glyceraldehyde: D = +; L = -
 D/L enantiomer: switch position of OH on every chiral C
 Cyclization to hemiacetal = nucleophilic addition
 Anomers:
o α = OH on anomeric C on opposite side as CH2OH
o β = OH on anomeric C on same side as CH2OH
 At equilibrium, anomer with OH on anomeric C in more stable equatorial position
present at higher abundance
 Hemiacetal = OH, OR will mutarotate
 Acetal = OR, OR will not mutarotate
 Acetal formation: hemiacetal + ROH (O-glycoside) or NR2H (N-glycoside)
o SN1 via C+ intermediate
o Makes both α and β but won’t mutarotate once formed

Fischer to Haworth:
i) Number carbons in Fischer
ii) Draw Haworth structure for aldose = pyranose (6-mem ring, including O) or ketose =
furanose (5-mem ring, including O with C1 branched off C2)
iii) Number carbons in Haworth ring
iv) Draw in C6: D = up, L = down
v) Draw in OH on anomeric C: α = opposite C6, β = same as C6
vi) Fill in remaining OH (right = down, left = up)
 Oxidation:


1

, o Bromine water = oxidize just aldehyde to COOH
o HNO3 = oxidize aldehyde and primary alcohol on C6 to COOH
 Reduction: reduce aldehyde to CH2OH or ketone to OH, H
o NaBH4
 Glucose = epimer of mannose = const. isomer of fructose
o Deprot Cα, will get mix of all 3
o Epimerization: Deprot Cα, form enolate C-/C=C, reprotonate Cα on opposite face
o Isomerization: 2 tautomerizations
 Deprot Cα, form C-, form O- (C=C), protonate O-, deprotonate other OH,
form C=O to form C-, protonate C-
 Aldol Reaction:
i) Deprot Cα
ii) C- attacks C=O of another equivalent
iii) Protonate O-
iv) Forms β hydroxy ketone
 Retro-aldol: cleave between α and β
Kiliani Fischer
 Extends chain one carbon at a time
 # rounds of synthesis = # carbons added just below C1 aldehyde
 Makes new chiral center: 2 products
 Step 1: nuc addition of CN- to carbonyl
 Historic:
o Aqueous acid to hydrolyze CN to COOH
o Spontaneously form lactone (cyclic ester)
o NaOH to hydrolyze to carboxylate salt
o Recrystalize salts (diastereomers with diff physical properties)
o Protonate COO- (forms lactone = cyclic ester)
o Reduce ester to aldehyde with Na/Hg
 Modern:
o Add H2 + Pd/BaSO4 catalyst to reduce nitrile to imine
o Add aqueous acid to hydrolyze imine to aldehyde
o Separate by HPLC
o Fewer steps / recrystallization / separations
o Fewer toxic reagents




2

, Disaccharides
 Disaccharides: two monosaccharides (aldoses or ketoses) connected via an acetal linkage
= glycoside
o At least one sugar’s anomeric carbon is involved in the acetal, though both may
be involved
 Acetals are cleaved by acid
 Acetals are stable in neutral and basic conditions (unlike hemiacetals)
 Acetals do not interconvert with their open chain forms
o Do not mutarotate
o Are not reducing
 If one part of the disaccharide molecule is a hemiacetal (ie., one anomeric carbon is not
involved in the acetal) then the whole molecule will mutarotate and will be a reducing
sugar
Disaccharides of D-Glucose: Maltose and Cellobiose
 Both have hemiacetals: mutarotate and are reducing
 Maltose joined by α 1,4
 Cellobiose joined by β 1, 4
Lactose
 Lactose = D-galactose + D-glucose joined β(1,4)
 Lactase aka. β-galactosidase cleaves lactose linkage
o Lactose intolerant individuals deficient in this enzyme
Sucrose
 Sucrose = D-glucose + D-fructose
o Linkage = α(1,2) at glucose, β(2, 1) at fructose
 No hemiacetals (both anomeric carbons involved in acetal) so does not mutarotate and is
not reducing
 Sucrose (disaccharide) = “invert sugar” because when hydrolyzed to monosaccharides
(glucose and fructose), the direction of optical rotation changes / inverts
o Sucrose rotates PPL +
o Glucose + fructose mixture rotates PPL –
 Glucose + fructose mixture is twice as sweet tasting than sucrose




3

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

Guaranteed quality through customer reviews

Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.

Quick and easy check-out

Quick and easy check-out

You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.

Focus on what matters

Focus on what matters

Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!

Frequently asked questions

What do I get when I buy this document?

You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.

Satisfaction guarantee: how does it work?

Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.

Who am I buying these notes from?

Stuvia is a marketplace, so you are not buying this document from us, but from seller oawn18. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for CA$58.07. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

79650 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 14 years now

Start selling

Recently viewed by you

Exam (elaborations) ·

(0)

CPN- Fluid And Electrolytes Questions And Answers With Verified Solutions Already 2024 /2025

Class notes ·

(0)

Introduction income statement
CA$58.07
  • (0)
  Add to cart