title: Proline editing: a general and practical approach to the synthesis of functionally and structurally diverse peptides. Analysis of steric versus stereoelectronic effects of 4-substituted prolines on conformation within peptides.
abstract: Functionalized proline residues have diverse applications. Herein we describe a practical approach, proline editing, for the synthesis of peptides with stereospecifically modified proline residues. Peptides are synthesized by standard solid-phase peptide synthesis to incorporate Fmoc-hydroxyproline (4R-Hyp). In an automated manner, the Hyp hydroxyl is protected and the remainder of the peptide synthesized. After peptide synthesis, the Hyp protecting group is orthogonally removed and Hyp selectively modified to generate substituted proline amino acids, with the peptide main chain functioning to "protect" the proline amino and carboxyl groups. In a model tetrapeptide (Ac-TYPN-NH2), 4R-Hyp was stereospecifically converted to 122 different 4-substituted prolyl amino acids, with 4R or 4S stereochemistry, via Mitsunobu, oxidation, reduction, acylation, and substitution reactions. 4-Substituted prolines synthesized via proline editing include incorporated structured amino acid mimetics (Cys, Asp/Glu, Phe, Lys, Arg, pSer/pThr), recognition motifs (biotin, RGD), electron-withdrawing groups to induce stereoelectronic effects (fluoro, nitrobenzoate), handles for heteronuclear NMR ((19)F:fluoro; pentafluorophenyl or perfluoro-tert-butyl ether; 4,4-difluoro; (77)SePh) and other spectroscopies (fluorescence, IR: cyanophenyl ether), leaving groups (sulfonate, halide, NHS, bromoacetate), and other reactive handles (amine, thiol, thioester, ketone, hydroxylamine, maleimide, acrylate, azide, alkene, alkyne, aryl halide, tetrazine, 1,2-aminothiol). Proline editing provides access to these proline derivatives with no solution-phase synthesis. All peptides were analyzed by NMR to identify stereoelectronic and steric effects on conformation. Proline derivatives were synthesized to permit bioorthogonal conjugation reactions, including azide-alkyne, tetrazine-trans-cyclooctene, oxime, reductive amination, native chemical ligation, Suzuki, Sonogashira, cross-metathesis, and Diels-Alder reactions. These proline derivatives allowed three parallel bioorthogonal reactions to be conducted in one solution.
authors: Department of Chemistry, Biochemistry, University of Delaware, Newark, Delaware 19716, USA.
authors: Anil K
authors: AK
authors: Pandey
authors: Devan
authors: D
authors: Naduthambi
authors: Krista M
authors: KM
authors: Thomas
authors: Neal J
authors: NJ
authors: Zondlo
mesh_terms: D000215:Acylation; D054879:Halogenation; D006909:Hydroxyproline / Q000138:chemical synthesis / Q000737:chemistry*; D008968:Molecular Conformation; D010084:Oxidation-Reduction; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry; D011392:Proline / Q000031:analogs & derivatives* / Q000138:chemical synthesis; D060327:Solid-Phase Synthesis Techniques / Q000379:methods*; D013057:Spectrum Analysis; D013237:Stereoisomerism; D013451:Sulfonic Acids / Q000138:chemical synthesis / Q000737:chemistry
chemical_list: D010455:Peptides; D013451:Sulfonic Acids; D011392:Proline; D006909:Hydroxyproline
references: Org Lett. 2001 Aug 9;3(16):2477-9
references: 11483039
references: J Am Chem Soc. 2012 Feb 29;134(8):3912-6
references: 22332757
references: Biopolymers. 2008 May;89(5):443-54
references: 17937398
references: Annu Rev Cell Dev Biol. 1996;12:697-715
references: 8970741
references: Biochemistry. 2009 Sep 29;48(38):9040-6
references: 19658436
references: Chembiochem. 2008 Aug 11;9(12):2000-4
references: 18655064
references: Chem Rev. 2005 Mar;105(3):793-826
references: 15755077
references: ChemMedChem. 2006 Jan;1(1):54-7
references: 16892335
references: Science. 2002 Dec 6;298(5600):1912-34
references: 12471243
references: J Pept Sci. 1998 Feb;4(1):1-14
references: 9523751
references: Biochemistry. 2006 May 2;45(17):5527-37
references: 16634634
references: Angew Chem Int Ed Engl. 2009;48(38):6974-98
references: 19714693
references: Angew Chem Int Ed Engl. 2006 Dec 11;45(48):8141-5
references: 17109457
references: J Am Chem Soc. 2002 Mar 20;124(11):2497-505
references: 11890798
references: J Biol Chem. 2010 Oct 8;285(41):31484-90
references: 20682783
references: Angew Chem Int Ed Engl. 2009;48(49):9312-4
references: 19890933
references: Nat Struct Biol. 2002 Jun;9(6):425-30
references: 11979279
references: NMR Biomed. 2011 Feb;24(2):114-29
references: 20842758
references: Chembiochem. 2012 Jan 23;13(2):259-70
references: 22213184
references: Proc Natl Acad Sci U S A. 2010 Jan 12;107(2):559-64
references: 20080719
references: J Nat Prod. 1996 Dec;59(12):1205-11
references: 8988607
references: Proc Natl Acad Sci U S A. 2002 Feb 19;99(4):1899-904
references: 11830645
references: J Biol Chem. 2003 Jan 3;278(1):645-50
references: 12399455
references: J Biol Chem. 2010 Apr 9;285(15):11039-44
references: 20147747
references: Biopolymers. 2009;92(5):387-98
references: 19373924
references: J Am Chem Soc. 2005 Dec 28;127(51):18121-32
references: 16366565
references: Nat Struct Biol. 1997 Jul;4(7):548-52
references: 9228947
references: J Am Chem Soc. 2011 Aug 3;133(30):11418-21
references: 21736333
references: J Am Chem Soc. 2004 Oct 20;126(41):13194-5
references: 15479052
references: Annu Rev Biochem. 1999;68:779-819
references: 10872466
references: J Med Chem. 1990 May;33(5):1459-69
references: 2329568
references: Org Lett. 2005 Jun 9;7(12):2397-400
references: 15932207
references: Chem Commun (Camb). 2003 Oct 21;(20):2606-7
references: 14594303
references: J Am Chem Soc. 2005 Aug 24;127(33):11798-803
references: 16104758
references: J Am Chem Soc. 2006 Sep 27;128(38):12430-1
references: 16984189
references: J Am Chem Soc. 2002 Dec 18;124(50):15030-7
references: 12475347
references: Prog Nucl Magn Reson Spectrosc. 2023 Nov-Dec;138-139:52-69
references: 38065668
references: J Mol Biol. 1994 Nov 4;243(4):754-66
references: 7966294
references: Nat Chem Biol. 2010 Aug;6(8):615-20
references: 20622857
references: Chemistry. 2011 Nov 25;17(48):13433-7
references: 22038655
references: Org Lett. 2003 Nov 13;5(23):4413-6
references: 14602013
references: J Am Chem Soc. 2009 Nov 18;131(45):16346-7
references: 19852502
references: J Am Chem Soc. 2012 Feb 15;134(6):2950-3
references: 22289053
references: J Am Chem Soc. 1996;118(49):12261-12266
references: 21451735
references: Nat Chem. 2009 Nov;1(8):630-4
references: 20161563
references: Biopolymers. 1998 Apr;45(5):381-94
references: 9530015
references: Angew Chem Int Ed Engl. 2011 Aug 29;50(36):8333-7
references: 21780257
references: J Am Chem Soc. 2002 Mar 13;124(10):2134-6
references: 11878965
references: J Mol Biol. 1992 Dec 5;228(3):725-34
references: 1469711
references: Biol Trace Elem Res. 2010 Jun;134(3):235-51
references: 20306235
references: J Am Chem Soc. 2006 Nov 1;128(43):13984-5
references: 17061854
references: J Am Chem Soc. 2011 Oct 5;133(39):15316-9
references: 21899368
references: Biochemistry. 2002 Feb 12;41(6):1897-905
references: 11827536
references: J Am Chem Soc. 2008 Mar 26;130(12):4028-33
references: 18321101
references: J Am Chem Soc. 2009 Sep 9;131(35):12497-515
references: 19689159
references: J Mol Biol. 1998 Jun 5;279(2):449-60
references: 9642049
references: J Org Chem. 2012 Jun 15;77(12):5331-44
references: 22607128
references: Chembiochem. 2011 May 2;12(7):1039-42
references: 21448869
references: J Med Chem. 1997 Nov 21;40(24):3947-56
references: 9397175
references: J Am Chem Soc. 2010 Oct 13;132(40):13957-9
references: 20849115
references: Chem Commun (Camb). 2011 Feb 14;47(6):1698-700
references: 21206952
references: J Am Chem Soc. 2009 Sep 23;131(37):13192-3
references: 19711980
references: Chem Rev. 2003 Jul;103(7):2475-532
references: 12848578
references: J Am Chem Soc. 2007 May 2;129(17):5665-72
references: 17417847
references: J Am Chem Soc. 2003 Sep 24;125(38):11500-1
references: 13129344
references: J Am Chem Soc. 2004 May 19;126(19):6048-57
references: 15137770
references: J Org Chem. 2005 Aug 5;70(16):6274-81
references: 16050687
references: J Am Chem Soc. 2005 Mar 9;127(9):2974-83
references: 15740134
references: Chem Soc Rev. 2012 Mar 21;41(6):2135-71
references: 22130572
references: Angew Chem Int Ed Engl. 2000 Mar;39(6):1111-1115
references: 10760936
references: J Am Chem Soc. 2011 Jul 20;133(28):10784-6
references: 21696220
references: J Am Chem Soc. 2003 Aug 20;125(33):9922-3
references: 12914445
references: J Am Chem Soc. 2008 Dec 10;130(49):16515-7
references: 19554688
references: J Org Chem. 2003 May 16;68(10):3923-31
references: 12737573
references: Org Lett. 2010 Dec 3;12(23):5390-3
references: 21049969
references: J Org Chem. 2007 Feb 16;72(4):1464-7
references: 17243713
references: Proteins. 2000 Aug 15;40(3):389-408
references: 10861930
references: Acc Chem Res. 2001 May;34(5):389-97
references: 11352717
references: J Mol Biol. 1991 Mar 20;218(2):397-412
references: 2010917
references: J Am Chem Soc. 2012 Jan 18;134(2):800-3
references: 22175226
references: J Am Chem Soc. 2001 Jan 31;123(4):777-8
references: 11456609
references: Sci STKE. 2003 Apr 22;2003(179):RE8
references: 12709533
references: J Fluor Chem. 2008 Sep;129(9):781-784
references: 19727323
references: J Am Chem Soc. 2005 Nov 16;127(45):15923-32
references: 16277536
references: J Am Chem Soc. 2002 Mar 27;124(12):3175-85
references: 11902907
references: Protein Sci. 1994 Dec;3(12):2207-16
references: 7756980
references: Angew Chem Int Ed Engl. 2008;47(31):5765-7
references: 18576439
references: Chemistry. 2005 Apr 8;11(8):2395-404
references: 15669065
references: Protein Sci. 2001 Dec;10(12):2627-32
references: 11714932
references: Angew Chem Int Ed Engl. 2001 Mar 2;40(5):923-925
references: 11241647
references: Chembiochem. 2009 Apr 17;10(6):959-69
references: 19343741
references: Org Biomol Chem. 2010 Apr 21;8(8):1881-4
references: 20449493
references: Proc Natl Acad Sci U S A. 1991 Jun 15;88(12):5317-20
references: 2052608
references: Science. 2011 Jun 17;332(6036):1401-3
references: 21680836
references: Proc Natl Acad Sci U S A. 2003 Oct 14;100(21):12075-80
references: 14507995
references: J Org Chem. 2007 Dec 7;72(25):9834-7
references: 17979289
references: J Am Chem Soc. 2005 Jul 6;127(26):9459-68
references: 15984873
references: Curr Opin Chem Biol. 2008 Dec;12(6):746-54
references: 18804173
references: J Am Chem Soc. 2003 Jun 25;125(25):7500-1
references: 12812474
references: Org Lett. 2011 Oct 21;13(20):5588-91
references: 21916452
references: Chembiochem. 2004 Jan 3;5(1):79-86
references: 14695516
references: Nat Chem. 2012 Feb 05;4(4):298-304
references: 22437715
references: J Am Chem Soc. 2002 Oct 2;124(39):11653-6
references: 12296730
references: Angew Chem Int Ed Engl. 2006 Nov 20;45(45):7581-4
references: 17051631
references: Acc Chem Res. 2013 Apr 16;46(4):1039-49
references: 23148796
references: J Am Chem Soc. 2010 Dec 1;132(47):16805-11
references: 21050005
references: J Mol Biol. 1999 Nov 19;294(1):271-88
references: 10556045
references: J Am Chem Soc. 2003 Jan 15;125(2):405-11
references: 12517152
references: J Org Chem. 2006 Jun 23;71(13):5004-7
references: 16776535
references: Curr Med Chem. 2004 Nov;11(21):2785-98
references: 15544476
references: Biopolymers. 2006;84(2):192-204
references: 16208767
references: J Mol Biol. 2003 Aug 22;331(4):925-40
references: 12909019
references: Chem Commun (Camb). 2010 Mar 14;46(10):1589-600
references: 20177591
references: Curr Opin Chem Biol. 2010 Dec;14(6):774-80
references: 21071259
references: J Am Chem Soc. 2012 Jan 18;134(2):792-5
references: 22176354
references: J Med Chem. 1991 Feb;34(2):717-25
references: 1671706
references: Bioorg Med Chem Lett. 2008 Feb 1;18(3):1096-101
references: 18083557
references: Chem Phys Lett. 2010 Mar 5;487(4-6):303-306
references: 20419080
references: Science. 1996 Jan 19;271(5247):342-5
references: 8553067
references: Chembiochem. 2010 Aug 16;11(12):1738-47
references: 20623571
references: J Comb Chem. 2004 Jan-Feb;6(1):91-8
references: 14714991
references: J Am Chem Soc. 2002 Jul 31;124(30):8876-83
references: 12137542
references: J Am Chem Soc. 2010 Nov 10;132(44):15708-13
references: 20961065
references: J Am Chem Soc. 2003 Aug 6;125(31):9262-3
references: 12889933
references: J Med Chem. 2009 Jun 25;52(12):3627-35
references: 19473029
references: J Am Chem Soc. 2006 Nov 15;128(45):14697-703
references: 17090057
references: Antioxid Redox Signal. 2007 Jul;9(7):775-806
references: 17508906
references: J Am Chem Soc. 2006 Feb 22;128(7):2216-7
references: 16478167
references: J Org Chem. 2005 Aug 5;70(16):6447-53
references: 16050708
references: Curr Opin Biotechnol. 2003 Dec;14(6):603-9
references: 14662389
references: Biopolymers. 1981 Feb;20(2):283-302
references: 33327685
references: Nucleic Acids Res. 2004 Feb 11;32(3):1037-49
references: 14960716
references: Org Lett. 2001 Aug 9;3(16):2481-4
references: 11483040
references: J Am Chem Soc. 2012 Feb 15;134(6):2898-901
references: 22283158
references: Biopolymers. 2005;80(1):1-8
references: 15558658
references: Proc Natl Acad Sci U S A. 2010 Nov 30;107(48):20636-41
references: 21068369
references: Curr Opin Chem Biol. 2008 Dec;12(6):760-6
references: 19058994
references: J Am Chem Soc. 1973 Aug 22;95(17):5725-9
references: 4733811
references: J Am Chem Soc. 2004 Jun 2;126(21):6759-64
references: 15161304
references: Curr Pharm Des. 2003;9(15):1209-24
references: 12769748
references: Nature. 2005 Nov 10;438(7065):248-52
references: 16281040
references: J Am Chem Soc. 2003 Mar 19;125(11):3192-3
references: 12630856
references: PLoS One. 2011;6(5):e19425
references: 21625626
references: Nat Struct Mol Biol. 2005 Jul;12(7):619-23
references: 15937494
references: Chem Rev. 2009 Jun;109(6):2551-651
references: 19382806
references: J Am Chem Soc. 2008 Oct 15;130(41):13518-9
references: 18798613
references: J Mol Biol. 1988 May 5;201(1):161-200
references: 2843644
references: Nature. 1999 Jun 24;399(6738):784-8
references: 10391244
references: J Med Chem. 1989 Jul;32(7):1600-6
references: 2544729
references: J Org Chem. 2001 Feb 9;66(3):1038-42
references: 11430070
references: J Am Chem Soc. 2008 Jul 16;130(28):9106-12
references: 18570424
references: Cell. 2003 Mar 21;112(6):859-71
references: 12654251
references: Biochemistry. 2007 Oct 30;46(43):12308-13
references: 17924662
references: J Med Chem. 1988 Jun;31(6):1148-60
references: 2836590
references: Nat Chem Biol. 2010 Aug;6(8):567-8
references: 20644541
references: J Am Chem Soc. 2003 Oct 1;125(39):11802-3
references: 14505386
references: Int J Pept Protein Res. 1990 Sep;36(3):285-91
references: 2279851
references: FASEB J. 2000 Feb;14(2):231-41
references: 10657980
references: Science. 1994 Nov 4;266(5186):776-9
references: 7973629
references: Angew Chem Int Ed Engl. 2008;47(11):2143-6
references: 18228549
references: Biochemistry. 1994 Oct 11;33(40):12022-31
references: 7918421
references: Bioorg Med Chem Lett. 2009 Jul 15;19(14):3859-62
references: 19423349
references: Org Biomol Chem. 2012 Sep 28;10(36):7241-61
references: 22890839
references: Org Biomol Chem. 2008 Aug 7;6(15):2655-65
references: 18633519
references: J Am Chem Soc. 2004 Nov 10;126(44):14334-5
references: 15521735
references: Chem Rev. 2009 Jun;109(6):2455-504
references: 19364121
references: J Am Chem Soc. 2003 Apr 23;125(16):4702-3
references: 12696876
references: J Org Chem. 1970 Jun;35(6):1924-7
references: 5446984
references: J Am Chem Soc. 2012 Jun 27;134(25):10317-20
references: 22694658
references: Biopolymers. 1976 Oct;15(10):2025-41
references: 963241
references: Chembiochem. 2004 Jul 5;5(7):928-36
references: 15239049
references: J Phys Chem B. 2012 May 3;116(17):5097-110
references: 22512849
references: Biochemistry. 2010 Jul 27;49(29):6290-5
references: 20565125
references: J Am Chem Soc. 2006 Jun 28;128(25):8112-3
references: 16787056
references: Chem Biol Drug Des. 2010 Feb;75(2):161-8
references: 20028399
references: J Nucl Med. 2004 May;45(5):892-902
references: 15136641
references: Biochemistry. 2010 May 18;49(19):4255-63
references: 20405858
references: J Am Chem Soc. 2004 Oct 6;126(39):12252-3
references: 15453743
references: J Am Chem Soc. 2008 Jul 30;130(30):9642-3
references: 18593118
references: J Am Chem Soc. 2002 Mar 20;124(11):2474-84
references: 11890796
references: J Am Chem Soc. 2006 May 3;128(17):5590-1
references: 16637598
references: Science. 2008 Mar 7;319(5868):1387-91
references: 18323453
references: J Am Chem Soc. 2010 Jan 13;132(1):321-7
references: 20050707
references: Chem Soc Rev. 2002 Nov;31(6):335-41
references: 12491748
references: J Am Chem Soc. 2011 Jun 29;133(25):9646-9
references: 21599005
references: J Org Chem. 2012 Apr 20;77(8):4131-5
references: 22428628
references: Adv Protein Chem. 2001;59:243-82
references: 11868274
references: Proteins. 2005 Feb 15;58(3):589-95
references: 15609336
references: Biochemistry. 2003 Aug 19;42(32):9515-24
references: 12911293
references: Protein Sci. 2003 Jun;12(6):1188-94
references: 12761389
references: J Mol Biol. 1993 Mar 20;230(2):543-74
references: 8464064
references: J Am Chem Soc. 2010 Apr 28;132(16):5619-21
references: 20361796
references: J Am Chem Soc. 2007 Jan 24;129(3):466-7
references: 17226990
references: Science. 2007 Sep 28;317(5846):1881-6
references: 17901324
references: Org Lett. 2006 Oct 12;8(21):4695-7
references: 17020280
references: Bioorg Med Chem Lett. 2011 Sep 1;21(17):5011-4
references: 21601452
references: Nat Struct Biol. 1997 Feb;4(2):112-4
references: 9033589
references: J Mol Biol. 1994 Nov 4;243(4):736-53
references: 7966293
references: Biochemistry. 2012 Jun 26;51(25):5041-51
references: 22667692
references: Biochim Biophys Acta. 2009 Nov;1790(11):1424-8
references: 19477234
references: J Med Chem. 1995 Jan 6;38(1):137-49
references: 7837225
references: Nat Prod Rep. 2002 Feb;19(1):49-59
references: 11902439
references: Nature. 1998 Apr 16;392(6677):666-7
references: 9565027
references: Science. 1997 Dec 12;278(5345):1957-60
references: 9395400
references: Org Lett. 2012 Jan 20;14(2):464-7
references: 22224916
references: Science. 2003 Nov 21;302(5649):1364-8
references: 14631033
references: Chemistry. 2012 Sep 3;18(36):11334-42
references: 22829538
references: Angew Chem Int Ed Engl. 2010 Aug 23;49(36):6324-7
references: 20665611
references: J Am Chem Soc. 2005 Nov 23;127(46):15998-9
references: 16287266
references: Glycobiology. 2012 Jun;22(6):757-67
references: 22190471
references: Chembiochem. 2010 Jul 26;11(11):1505-7
references: 20572253
references: J Am Chem Soc. 2001 Mar 7;123(9):2079-80
references: 11456840
references: J Med Chem. 2000 Dec 28;43(26):4948-63
references: 11150165
references: J Biol Chem. 2010 Mar 19;285(12):8976-84
references: 20068044
references: Annu Rev Biochem. 2010;79:413-44
references: 20307192
references: Biochemistry. 2002 May 14;41(19):6054-64
references: 11994000
references: Bioorg Med Chem Lett. 2007 May 15;17(10):2765-8
references: 17363245
references: Biopolymers. 1997;43(3):219-66
references: 9277134
references: Annu Rev Biophys Biomol Struct. 1993;22:199-232
references: 8347989
references: Nature. 2008 May 8;453(7192):190-5
references: 18354394
references: Chem Commun (Camb). 2009 Jun 21;(23):3366-8
references: 19503872