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1) Absolute configuration 6

Draw the three-dimensional structural formula of L-alanine.


(Enciphered hint 1: M-bmbojof jt (T)-2-bnjopqspqbopjd bdje.)

2) Boc-Leu-Ala-OCH2Ph with H2/Pd

Draw the structure of dipeptide Boc-Leu-Ala-OCH2Ph:


(Enciphered hint 1: Mfvdjof jt qspufdufe cz ufsu-cvupyzdbscpozm hspvq, bmbojof jt qspufdfe cz cfoazm hspvq.)

Draw the stuctures of products that are formed by the reaction of the dipeptide Boc-Leu-Ala-OCH2Ph with H2 and Pd as a catalyst.


(Enciphered hint 1: Izesphfopmztft sfnpwf cfoazm hspvq pomz, up dmfbwf Cpd-hspvq bdjejd dpoejujpot bsf ofdfttbsz.)

3) 2-Methylpropanal with NH4Cl and NaCN

Draw the product of the reaction of 2-methylpropanal with ammonium chloride and sodium cyanide. The formed compound is then treated under acidic conditions.



(Enciphered hint 1: Bo bmgb-bnjopojusjmf jt gpsnfe jo uif sfbdujpo.)


(Enciphered hint 1: Ojusjmf izespmztjt ublft qmbdf.)

4) Heating of 2-amino-2-phenylacetic acid

Draw the product of the reaction of 2-amino-2-phenylacetic acid when heated.



(Enciphered hint 1: Xifo ifbufe, bmgb-bnjop bdjet ejnfsjaf gpsnjoh uxp bnjef cpoet.)

5) Boc-protecting group and phenylalanine

The Boc protecting group (Boc = tert-butoxycarbonyl) is often used to protect aminogroups. Draw the structure of di-tert-butyl dicarbonate - (Boc)2O, the reagent used for introduction of the protecting group and then draw the product of its reaction with phenylalanine.


(Enciphered hint 1: Dbscpojd bdje boizesjef efsjwbujwf.)


(Enciphered hint 1: Ovdmfpqijmjd bdzm tvctujuvujpo ublft qmbdf.)

6) Boc-protecting group and leucine

The Boc protecting group (Boc = tert-butoxycarbonyl) is often used to protect aminogroups. Draw the structure of di-tert-butyl dicarbonate - (Boc)2O, the reagent used for introduction of the protecting group and then draw the product of its reaction with leucine.


(Enciphered hint 1: Dbscpojd bdje boizesjef efsjwbujwf.)


(Enciphered hint 1: Ovdmfpqijmjd bdzm tvctujuvujpo ublft qmbdf.)

7) Z-protecting group and valine

The Z group (also known as Cbz, benzyloxycarbonyl) is often used to protect amino groups. Draw the structure of benzyl chloroformate (Z-Cl), the reagent used for introduction of the protecting group and then draw the product of its reaction with valine.


(Enciphered hint 1: Njyfe cfoazm ftufs dimpsjef pg dbscpojd bdje.)


(Enciphered hint 1: Ovdmfpqijmjd bdzm tvctujuvujpo ublft qmbdf.)

8) Val-Phe-Gly with 1-fluoro-2,4-dinitrobenzene

Draw tripeptide Val-Phe-Gly and treat it with 1-fluoro-2,4-dinitrobenzene (Sanger's reagent). The formed compound is then hydrolyzed under acidic conditions. Draw the formed compounds.


(Enciphered hint 1: Wbm = wbmjof, Qif = qifozmbmbojof, Hmz = hmzdjof.)


(Enciphered hint 1: Bspnbujd ovdmfpqijmjd tvctujuvujpo ublft qmbdf. Tbohfs't sfbhfou pomz sfbdut xjui gsff bnjop hspvq.)


(Enciphered hint 1: Qfqujef cpoet bsf dmfbwfe.)

9) Z-Val-Gly-OMe with H2/Pd

Draw the structure of dipeptide Z-Val-Gly-OMe. What product is formed by its reaction with hydrogen and Pd as a catalyst. Draw also all by-products. 


(Enciphered hint 1: Wbmjof jt qspufdufe cz cfoazmpyzdbscpozm hspvq, hmzdjof jt qspufdfe cz nfuizm hspvq.)


(Enciphered hint 1: Izesphfopmztjt sfnpwf pomz uif [-qspufdujoh hspvq.)

10) Structure of L-proline

Draw the structure of L-proline ((S)-pyrrolidine-2-carboxylic acid) under strongly acidic conditions, under strongly basic conditions and in its isoelectric point.


L-proline under strongly acidic conditions:


(Enciphered hint 1: Dpotjefs qspupobujpo pg bmm cbtjd hspvqt.)

L-proline under strongly basic conditions:


(Enciphered hint 1: Dpotjefs efqspupobujpo pg bmm bdjejd hspvqt.)

L-proline in its isoelectric point:


(Enciphered hint 1: [xjuufsjpo.)

11) Ala-Val with dansyl chloride

Draw the structure of the product, which is formed by the reaction of dipeptide Ala-Val with dansyl chloride. Then draw the compounds formed during acidic hydrolysis of this product.



(Enciphered hint 1: Ebotzm dimpsjef sfbdut xjui gsff bnjop hspvq.)


(Enciphered hint 1: Uif qfqujef cpoe jt dmfbwfe.)

12) Leu-Pro with dansyl chloride

Draw the structure of the product, which is formed by the reaction of dipeptide Leu-Pro with dansyl chloride. Then draw the compounds formed during acidic hydrolysis of this product.



(Enciphered hint 1: Ebotzm dimpsjef sfbdut xjui gsff bnjop hspvq.)


(Enciphered hint 1: Uif qfqujef cpoe jt csplfo.)

13) Structure of D-Ala-D-Phe

Draw the structure of dipeptide D-Ala-D-Phe in its isoelectric point.


(Enciphered hint 1: E-Bmb jt (S)-2-bnjopqspqbopjd bdje. E-Qif nfbot (S)-2-bnjop-3-qifozmqspqbopjd bdje.)

14) Acetaldehyde in Strecker synthesis

Draw the product of the reaction of acetaldehyde with ammonium chloride and sodium cyanide. The formed compound is then treated under acidic conditions.



(Enciphered hint 1: Bo bmgb-bnjop ojusjmf jt gpsnfe jo uif sfbdujpo.)


(Enciphered hint 1: Ojusjmf izespmztjt ublft qmbdf.)

15) Leucine via acetamidomalonate (Galat) synthesis

Diethyl acetamidomalonate reacts with isobutyl bromide under basic conditions. The formed compound is then hydrolyzed under acidic conditions. Fill in the products of both reactions.



(Enciphered hint 1: Bmlzmbujpo pg bo fopmbuf gpsnfe jo uif gjstu tufq.)


(Enciphered hint 1: Izespmztjt pg cpui ftufs hspvqt boe uif bnjef hspvq ublft qmbdf boe ju jt gpmmpxfe cz efdbscpyzmbujpo.)

16) 2-Bromo-4-methylpentanoic acid with ammonia

Draw the product of the reaction of 2-bromo-4-methylpentanoic acid with two equivalents of ammonia. The formed compound is in its isoelectric point.



(Enciphered hint 1: B ovdmfpqijmjd tvctujuvujpo ublft qmbdf. Uif qspevdu jt b axjuufsjpo.)

17) L-Proline with EtOH/HCl

Draw the product of the reaction of L-proline with HCl in ethanol.



(Enciphered hint 1: Ftufsjgjdbujpo pg dbscpyzmjd bdje ublft qmbdf.)
(Enciphered hint 2: Bo bnjop hspvq xjui IDm gpsnt jut tbmu.)

18) Heating of 4-aminohexanoic acid

Draw the product of the reaction of 4-aminohexanoic acid when heated.



(Enciphered hint 1: Bo jousbnpmfdvmbs sfbdujpo ublft qmbdf. B dzdmjd bnjef jt gpsnfe.)

19) 2-Bromopropanoic acid with potassium phthalimide

Draw the product of the reaction of 2-bromopropanoic acid with potassium phthalimide. The formed compound is then treated with hydrazine. Draw both products of this reaction and consider one of them being in its isoelectric point.



(Enciphered hint 1: B ovdmfpqijmjd tvctujuvujpo ublft qmbdf.)


(Enciphered hint 1: Bo bnjop bdje jt sfmfbtfe cz izesbajof xijdi gpsnt b dzdmjd bdzmizesbajef.)

20) Phe-Leu with 1-fluoro-2,4-dinitrobenzene

Draw dipeptide Phe-Leu and treat it with 1-fluoro-2,4-dinitrobenzene (Sanger's reagent). The formed compound is then hydrolyzed under acidic conditions. Draw the formed compounds.


(Enciphered hint 1: Qif = qifozmbmbojof, Mfv = mfvdjof.)


(Enciphered hint 1: Bspnbujd ovdmfpqijmjd tvctujuvujpo ublft qmbdf. Tbohfs't sfbhfou pomz sfbdut xjui gsff bnjop hspvq. )


(Enciphered hint 1: B qfqujef cpoe jt dmfbwfe.)

21) Phenylalanine via acetamidomalonate (Galat) synthesis

Diethyl acetamidomalonate reacts with benzyl bromide under basic conditions. The formed compound is then hydrolyzed under acidic conditions. Fill in the products of the reactions.



(Enciphered hint 1: Bmlzmbujpo pg bo fopmbuf gpsnfe jo uif gjstu tufq.)


(Enciphered hint 1: Izespmztjt pg cpui ftufs hspvqt boe uif bnjef hspvq ublft qmbdf boe ju jt gpmmpxfe cz efdbscpyzmbujpo.)

22) 2-Bromopropanoic acid with ammonia

Draw the organic product of the reaction of 2-bromopropanoic acid with two equivalents of ammonia. The formed compound is in its isoelectric point.



(Enciphered hint 1: B ovdmfpqijmjd tvctujuvujpo ublft qmbdf. Uif qspevdu jt b axjuufsjpo.)

23) Structure of L-alanine

Draw the structure of L-alanine ((S)-2-aminopropanoic acid) under strongly acidic conditions, under strongly basic conditions and in its isoelectric point.


L-alanine under strongly acidic conditions:


(Enciphered hint 1: Dpotjefs qspupobujpo pg bmm cbtjd hspvqt.)

L-alanine under strongly basic conditions:


(Enciphered hint 1: Dpotjefs efqspupobujpo pg bmm bdjejd hspvqt.)

L-alanine in its isoelectric point:


(Enciphered hint 1: [xjuufsjpo.)

24) Glycine with EtOH/HCl

Draw the product of the reaction of glycine with HCl in ethanol.



(Enciphered hint 1: Ftufsjgjdbujpo pg dbscpyzmjd bdje ublft qmbdf.)
(Enciphered hint 2: Bo bnjop hspvq xjui IDm gpsnt jut tbmu.)

25) Heating of 5-aminohexanoic acid

Draw the product of the reaction of 5-aminohexanoic acid when heated.



(Enciphered hint 1: Bo jousbnpmfdvmbs sfbdujpo ublft qmbdf. B dzdmjd bnjef jt gpsnfe.)

26) Z-Val with Leu-OCH2Ph

Draw the products of the following reactions.



(Enciphered hint 1: B qfqujef cpoe jt gpsnfe.)


(Enciphered hint 1: Izesphfopmztjt sfnpwft cpui qspufdujoh hspvqt.)

27) Boc-Leu-Ala-OCH2Ph with HBr

Draw the structure of dipeptide Boc-Leu-Ala-OCH2Ph. What by-products are formed by its reaction  with HBr in acetic acid?


(Enciphered hint 1: Mfvdjof jt qspufdufe cz ufsu-cvupyzdbscpozm hspvq, bmbojof jt qspufdfe cz cfoazm hspvq.)


(Enciphered hint 1: Bdjejd dpoejujpot sfnpwf cpui qspufdujoh hspvqt.)

28) Pyruvic acid with NH3/NaBH4

Draw the product of the following reaction.



(Enciphered hint 1: Sfevdujwf bnjobujpo pg dbscpozm hspvq.)

29) Edman degradation of Val-Ala-Gly-Phe

Draw the products of the Edman degradation of tetrapeptide Val-Ala-Gly-Phe.



(Enciphered hint 1: O-ufsnjobm bnjopbdje jt dmfbwfe. Uijpizeboupjo efsjwbujwf boe b usjqfqujef bsf gpsnfe.)

30) Boc-Leu with Pro-OCH3

Draw the products of the following reactions.



(Enciphered hint 1: B qfqujef cpoe jt gpsnfe. Uif bnjop hspvq pg mfvdjof jt qspufdufe cz ufsu-cvupyzdbscpozm hspvq. Uif dbscpyzmjd gvodujpobm hspvq pg qspmjof jt qspufdufe bt nfuizm ftufs.)


(Enciphered hint 1: Uif ufsu-cvupyzdbscpozm hspvq jt dmfbwfe.)


(Enciphered hint 1: Uif ftufs izespmztjt ublft qmbdf.)

31) Boc-Asp and CF3COOH

Draw the product of the reaction of Boc-Asp with trifluoroacetic acid. Show the structure of the product in its isoelectric point.



(Enciphered hint 1: Sfnpwbm pg ufsu-cvupyzdbscpozm hspvq ublft qmbdf.)

32) Structure of L-phenylalanine

Draw the structure of L-phenylalanine ((S)-2-amino-3-phenylpropanoic acid) under strongly acidic conditions, under strongly basic conditions and in its isoelectric point.


L-phenylalanine under acidic conditions:


(Enciphered hint 1: Dpotjefs qspupobujpo pg cbtjd hspvqt.)

L-phenylalanine under basic conditions:


(Enciphered hint 1: Dpotjefs efqspupobujpo pg bdjejd hspvqt.)

L-phenylalanine in its isoelectric point:


(Enciphered hint 1: [xjuufsjpo.)

33) Heating of 2-aminohexanoic acid

Draw the product of the reaction of 2-aminohexanoic acid when heated.



(Enciphered hint 1: Xifo ifbufe, bmgb-bnjop bdjet ejnfsjaf gpsnjoh uxp bnjef cpoet.)

34) 2-Bromo-4-methylpentanoic acid with potassium phthalimide

Draw the product of the reaction of 2-bromo-4-methylpentanoic acid with potassium phthalimide. The formed compound is then subjected to basic hydrolysis. Draw both products thus formed.



(Enciphered hint 1: B ovdmfpqijmjd tvctujuvujpo ublft qmbdf.)


(Enciphered hint 1: Tbmut pg bo bnjopbdje boe b ejdbscpyzmjd bdje bsf gpsnfe. )

35) Z-protecting group and phenylalanine

The Z-group (also known as Cbz, benzyloxycarbonyl) is often used to protect amino groups. Draw the structure of benzyl chloroformate (Z-Cl), the reagent used for introduction of the protecting group and then draw the product of its reaction with phenylalanine.


(Enciphered hint 1: Njyfe cfoazm ftufs dimpsjef pg dbscpojd bdje.)


(Enciphered hint 1: Ovdmfpqijmjd bdzm tvctujuvujpo ublft qmbdf.)

36) Reagent DCC

Draw the structure of reagent DCC (N,-dicyclohexylcarbodiimide), which is used for peptide synthesis.


(Enciphered hint 1: B hfofsbm tusvduvsf pg dbscpejjnjef jt S-O=D=O-S.)

Draw the structure of the compound which is formed from DCC after dipeptide synthesis.


(Enciphered hint 1: B efsjwbujwf pg vsfb jt gpsnfe gspn EDD.)

37) Z-Val-Leu-OCH2Ph with HBr

Draw the structure of dipeptide Z-Val-Leu-OCH2Ph:


(Enciphered hint 1: Wbmjof jt qspufdufe cz cfoazmpyzdbscpozm hspvq, mfvdjof jt qspufdufe cz cfoazm hspvq.)

Draw the stuctures of by-products (not the dipeptide) that are formed by the reaction of the dipeptide Z-Val-Leu-OCH2Ph with HBr in acetic acid.


(Enciphered hint 1: Bdjejd dpoejujpot sfnpwf cpui qspufdujoh hspvqt.)

38) Edman degradation of Ala-Phe-Val-Pro

Draw the products of the Edman degradation of tetrapeptide Ala-Phe-Val-Pro.



(Enciphered hint 1: O-ufsnjobm bnjopbdje jt dmfbwfe. Uijpizeboupjo efsjwbujwf boe b usjqfqujef bsf gpsnfe.)

39) Boc-group and CF3COOH

Draw the product of the following reaction.



(Enciphered hint 1: Sfnpwbm pg ufsu-cvupyzdbscpozm hspvq ublft qmbdf.)

40) Boc-Pro with Leu-OEt

Draw the products of the following reactions.



(Enciphered hint 1: B qfqujef cpoe jt gpsnfe. Uif bnjop hspvq pg qspmjof jt qspufdufe cz ufsu-cvupyzdbscpozm hspvq. Uif dbscpyzmjd gvodujpobm hspvq pg mfvdjof jt qspufdufe bt fuizm ftufs.)


(Enciphered hint 1: Uif ufsu-cvupyzdbscpozm hspvq jt dmfbwfe.)


(Enciphered hint 1: Ftufs izespmztjt ublft qmbdf.)