华南师范大学：《有机化学》课程PPT教学课件（双语版）Chapter 25 Nucleic acids and Protein synthesis

CHAPTER 25 NUCLEIC ACIDS AND PROTEIN SYNTHESIS 25.1 NTRODUCTION The nucleic acids, deoxyribonucleic (dna)and ribonucleic (RNA), are, respectively, the molecules that preserve here ditary information and that transcribe and translate it in a way that allows the synthesis of all the varied proteins of the cell 252 NUCLEOTIDES AND NUCLEOSIDES

CHAPTER 25 NUCLEIC ACIDS AND PROTEIN SYNTHESIS 25.1 INTRODUCTION The nucleic acids, deoxyribonucleic (DNA) and ribonucleic (RNA) , are, respectively , the molecules that preserve here￾ditary information and that transcribe and translate it in a way that allows the synthesis of all the varied proteins of the cell 25.2 NUCLEOTIDES AND NUCLEOSIDES

Mild degradations of nucleic acids yield their monomeric units compounds that are called nucleotides Heterocyclic base NI HO-POH,C B-N-Glycosidic HO-POH2C 9N"4N link OHOH OH OH A nucleotide Adenylic acid (核苷) (腺苷酸) Complete hydrolysis of a nucleotide furnishes 1. A heterocyclic base, either a purine or pyrimidine 2. a five-carbon monosaccharide, either D-ribose or 2-deoxy D-ribose 3.A phosphate ion

Mild degradations of nucleic acids yield their monomeric units, compounds that are called nucleotides. O POH2 C OH OH N O HO HO 1' 3' 2' 4' 5' Heterocyclic base -N-Glycosidic linkage  O POH2C OH OH O HO HO 1' 3' 2' 4' 5' N N N N NH2 1 2 3 4 5 7 6 8 9 Adenylic acid ( 腺苷酸) A nucleotide (核苷) Complete hydrolysis of a nucleotide furnishes: 1. A heterocyclic base, either a purine or pyrimidine. 2. a five-carbon monosaccharide, either D-ribose or 2-deoxy￾D-ribose. 3. A phosphate ion

The central portion of the nucleotide is the monosaccharide and it is always present as a five-membered ring, that is, as a furanoside The nucleosides that can be obtained from dna all contain 2-deoxy D-ribose as their sugar component and one of four heterocyclic bases either adenine, guanine, cytosine or thymine NHA NH NH H H,C H N NH H H H Adenine Guanine Cytosine Thymine (腺嘌呤) (鸟嘌呤) (胞核嘧啶) (胸腺嘧啶) Purines Pyrimidines

The central portion of the nucleotide is the monosaccharide and it is always present as a five-membered ring, that is, as a furanoside. The nucleosides that can be obtained from DNA all contain 2-deoxy￾D-ribose as their sugar component and one of four heterocyclic bases, either adenine, guanine, cytosine, or thymine. N N N N NH2 H N N N N NH H H NH2 N N NH2 O O O H H3 C H H Adenine (腺嘌呤) Guanine (鸟嘌呤) Cytosine (胞核嘧啶) Thymine (胸腺嘧啶) Purines Pyrimidines

The nucleosides obtained from RNa contain D-ribose as their sugar component and either adenine, guanine, cytosine, or uracil as their heterocyclic base H Uracil (尿嘧啶) Nucleotides are named in several ways. Adenylic acid for example is sometimes called 5-adenylic acid, it is also called 5-phosphate or simply adenosine monophosphate(AMP)

The nucleosides obtained from RNA contain D-ribose as their sugar component and either adenine, guanine, cytosine, or uracil as their heterocyclic base. N N O O H H Uracil (尿嘧啶) Nucleotides are named in several ways. Adenylic acid, for example, is sometimes called 5’-adenylic acid, it is also called 5’-phosphate, or simply adenosine monophosphate(AMP)

The names and structures of the nucleoside found in dna and rna Thymine Cytosine NH2 H3C N N CH,OH CHoOH H OH H 2-Deoxvcvtidine 2-Deoxythymidine Guanine Adenine NH2 N CH,OH CHOH NH, O H H H OH OH H 2-Deoxyguanosine 2'-Deoxyadenosine (2-脱氧次黄苷) (2-脱氧腺苷)

The names and structures of the nucleoside found in DNA and RNA: N N N N NH2 O O O H3C H Cytosine Thymine O CH2OH OH H H H H H O CH2OH OH H H H H H 2'-Deoxycytidine 2'-Deoxythymidine Adenine Guanine O CH2OH OH H N N N N NH2 H H H H O CH2OH OH H N N N N O H H H H H NH2 2'-Deoxyadenosine (2'-脱氧腺苷) 2'-Deoxyguanosine (2'-脱氧次黄苷)

Guanine Adenine H CHOH CH,OH NH2 H H H OH OH Guanosine Adenosine (鸟苷) (腺苷) Thymine Cytosine H CHOH CH,OH O H H OH OH H Cytidine Uridine (胞啶) (尿苷

N N N N NH2 O O O H3 C H Adenine Guanine Cytosine Thymine O CH2OH OH OH N N N N NH2 H H H H O CH2OH OH OH N N N N O H H H H H NH2 O CH2OH OH OH H H H H O CH2OH OH OH H H H H Adenosine (腺苷) Guanosine (鸟苷) Cytidine (胞啶) Uridine (尿苷)

253 LABORATORY SYNTHESIS OF NUCLEOSIDES AND NUCLEOTIDES One technique uses reaction that assemble the nucleoside from suitably activated and protected ribose derivatives and heterocyclic vase NHCOCH3 NHCOCH CH2OCOCH3 H n - y CH2OCOCH3N N H20-Adenosine OH OCOCH3 OCOCH3 Hgcl COCH COCH Another technique involves formation of the heterocyclic base on a protected ribosylamine derivative

25.3 LABORATORY SYNTHESIS OF NUCLEOSIDES AND NUCLEOTIDES One technique uses reaction that assemble the nucleoside from suitably activated and protected ribose derivatives and heterocyclic base. N N N N NHCOCH3 HgCl O CH2OCOCH3 OCOCH3 OCOCH3 H Cl + -HgCl 2 N N N N NHCOCH3 O CH2OCOCH3 OCOCH3 OCOCH3 OH - H2O Adenosine Another technique involves formation of the heterocyclic base on a protected ribosylamine derivative

O C6HsOCOH,C NH O H2 HC NH_(-2C2HsOH) hao Uridine OCOCkH CH C=O C6HsOCOH2C OCOC6H5 OCHs OC2H5 OCOC6H5 OCOC6H5 The third technique involves the synthesis of a nucleosides with a substituent in the heterocyclic ring that can be replaced with other NH, groups H CH,OH R H OHOH N

O C6H5OCOH2C OCOC6H5 OCOC6H5 NH2 + OH - H2O HC Uridine CH OC2H5 C NH O C O OC2H5 (-2C2H5OH) O C6H5OCOH2C OCOC6H5 OCOC6H5 N N O O H The third technique involves the synthesis of a nucleosides with a substituent in the heterocyclic ring that can be replaced with other groups. O CH2OH OH OH N N N N Cl H H H H NH3 H2 S Ni N N N N NH2 R N N N N S R H N N N N R R =

Specific phosphorylation of the 5-oH can be achieved if the 2,-and 3-oh groups of the nucleoside are protected by an isopropylidene group CHOH +(CHs O)P-Cl -udine(C6HsH2 CO)2POH2C HO-POH2C base H3C CH3 (1)H3O+,H2O (2)H2/Pd OH OH 25.3A MEDICAL APPLCATIONS

Specific phosphorylation of the 5’-OH can be achieved if the 2’- and 3’-OH groups of the nucleoside are protected by an isopropylidene group. O CH2OH O O H3 CH3 C base + (C6H5CH2O) 2P _ Cl O Pytidine O (C6H5H2 CO) 2 POH2 C O O H3C CH3 base O (1) H3O+, H2O (2) H2 / Pd O POH2C OH OH base O HO HO 25.3A MEDICAL APPLCATIONS

The discovering of the 6-mercaptopurine led to the development of other purine derivatives and related compounds. For example SH OH H HaNN N H H 6-Mercaptopurine Allopurinol Acyclovir (6-巯(基熛嘌呤) (别嘌呤醇) 25.4 DEOXYRIBONUCLEIC ACID: DNA 25,4A PRIMARY STRUCTURE Nucleotides bear the same relation to a nucleic acid that amino acids do to a protein; they are its monomeric units

The discovering of the 6-mercaptopurine led to the development of other purine derivatives and related compounds. For example: N N N N H SH N N N N H OH N N N N O O HO H H2N 6-Mercaptopurine (6-巯(基)嘌呤) Allopurinol (别嘌呤醇) Acyclovir 25.4 DEOXYRIBONUCLEIC ACID: DNA 25.4A PRIMARY STRUCTURE Nucleotides bear the same relation to a nucleic acid that amino acids do to a protein; they are its monomeric units