686
INDEX
Hydrogen bonds (continued )
in α-helix 511
imidazole 435
in β-pleated sheet 509–10
in protein tertiary structure 513
pyrazole 435
salicyclic acid 133
in secondary structure of proteins 509
in water 50
Hydrogen cyanide
acidity 128
bonding molecular orbitals 35
Hydrogen exchange
carboxylic acid derivatives 374
enols and enolate anions 351
hydroxyl groups 158
indole 443
oxazolium and thiazolium salts 437
Hydrogen halides
acidity 125
addition to alkenes 284–6
addition to alkynes 292–4
Hydrogen molecule, molecular orbitals 24
Hydrogenation, catalytic 332
Hydrolysis, β-ketoesters 387
Hydronium cation 34, 121
acidity 136
formal charge 47
Hydroperoxides 334
in autoxidation of fats 335
Hydrophobic interactions, in protein tertiary
structure 512
Hydroxyacid–lactone equilibria, Table 255
β-Hydroxyacyl-CoA dehydrogenase, in fatty
acid β-oxidation 591
Hydroxyaldehyde–hemiacetal equilibria,
Table 226
Hydroxydiazines, tautomerism 429
Hydroxyleucine, structure 503
β-Hydroxy-β-methylglutaryl-CoA, see
HMG-CoA
Hydroxyproline, structure 503
5-Hydroxytryptamine (5-HT, serotonin)
structure 446
receptors, 446
biosynthesis 602
5-Hydroxytryptophan
decarboxylation to 5-hydroxytryptamine
602
structure 602
Hyoscyamine
base hydrolysis 376
biological activity of enantiomers 78
racemization 77, 375
stereochemistry and shape 117
as tropane alkaloid 370
Hypoxanthine, in purine metabolism 451
Hysocine, stereochemistry and shape 117
Ibuprofen
biological activity of enantiomers 79
metabolic racemization 377
nomenclature 13
synthesis 314
Idose
Fischer projection 104
structure and stereochemistry 465
Iduronic acid, in heparin 496
Imidazole
basicity 143, 433
Chichibabin reaction 437
hydrogen bonding 435
molecular structure 432
reactivity 432
structure 432
Imidazole ring, tautomerism 517
Imidazoles, tautomerism 433
Imines
from aldehydes and ketones 242–7
in aldolase mechanism 526
as carbonyl analogues 243, 369
basicity 138
formation, comparison with acetal
formation 243
formation, intramolecular 245
formation, mechanism 242
electronic structure 34
in enzyme binding 516
hydrolysis 243
reduction with complex metal hydrides 246
in reductive amination 598
in Strecker synthesis of amino acids 245
Imine–enamine tautomerism, in
transamination 599
Imino acid, proline 499
Indole
acidity 445
aldol-like reactions 445
alkylation 445
basicity 443
electrophilic substitution 444
Fischer synthesis 461
hydrogen exchange 443
in Mannich reactions 445
in Michael reactions 445
reactivity 443–6
systematic name 439
Indole-3-acetic acid, structure 447
Inductive effect
influence on acidity 125–7
influence on basicity 137
definition 37
in electrophilic aromatic substitution 310
from functional groups, Table 126
Inhibitors
aminoacyl-tRNA binding 558
enzyme, see enzyme inhibitors
transcription 558
translation 558
Initiation step, radical chain reaction 323
Inosine phosphate, in nucleotide biosynthesis
563
myo-Inositol, conformational isomers 70
Insulin 486
biosynthesis 507
bovine, structure 507
disulfide bridges 507
human, structure 507
porcine, structure 507
Intermediary metabolism, definition 573
Intermediates
definition 173
energy diagram 174
International Union of Pure and Applied
Chemistry, see IUPAC
Intramolecular aldol reaction, see aldol
reaction
Intramolecular Claisen reaction, see Claisen
reaction
Intramolecular electrophilic addition 300
Inulin, structure 484
Inversion
at nitrogen 74
in S N 2 reactions 183, 190
Invert sugar 231
Invertase 231
Ion 19
Ionic bonding, see bonding, ionic
Ionic reactions 167–71
Ionization
amino acids at pH 7 150
calculation 150
morphine 163
Ionization constant, water
K w 135
temperature dependence 146
Ionization potential 23
Irreversible reactions, of carbonyl group 223
Isoborneol, in synthesis of camphor 219
Isocitrate, in Krebs cycle 586
Isocitrate dehydrogenase, in Krebs cycle 389,
587
Isodihydrocarvone, interconversion with
dihydrocarvone 353
Isoelectric point pI
alanine, calculation 161
amino acids, calculation 160
definition 160
glutamic acid, calculation 161
lysine, calculation 161
morphine 163
Isoleucine, structure and pK a values 500
Isoliquiritigenin, synthesis by aldol reaction
306
Isomers
configurational see configurational isomers
conformational see conformational isomers
constitutional 56
geometric 83
optical see optical isomers
structural 56
Isomerase, in unsaturated fatty acid
metabolism 593
Isomerism, cis –trans 30, 40
Isomerization, of glucose 467
Isopenicillin N
in penicillin biosynthesis 376
as precursor of β-lactam antibiotics 537
Isopentenyl diphosphate, in terpenoid and
steroid biosynthesis 300
Isoquinoline
basicity 442
Bischler–Napieralski synthesis 459
Chichibabin reaction 443
nucleophilic substitution 443
reactivity 442
systematic name 439
Isoquinolone 443
Isothiazole
basicity 438
structure 432
Isotopic labelling
carboxylic acid derivatives 374
INDEX
Hydrogen bonds (continued )
in α-helix 511
imidazole 435
in β-pleated sheet 509–10
in protein tertiary structure 513
pyrazole 435
salicyclic acid 133
in secondary structure of proteins 509
in water 50
Hydrogen cyanide
acidity 128
bonding molecular orbitals 35
Hydrogen exchange
carboxylic acid derivatives 374
enols and enolate anions 351
hydroxyl groups 158
indole 443
oxazolium and thiazolium salts 437
Hydrogen halides
acidity 125
addition to alkenes 284–6
addition to alkynes 292–4
Hydrogen molecule, molecular orbitals 24
Hydrogenation, catalytic 332
Hydrolysis, β-ketoesters 387
Hydronium cation 34, 121
acidity 136
formal charge 47
Hydroperoxides 334
in autoxidation of fats 335
Hydrophobic interactions, in protein tertiary
structure 512
Hydroxyacid–lactone equilibria, Table 255
β-Hydroxyacyl-CoA dehydrogenase, in fatty
acid β-oxidation 591
Hydroxyaldehyde–hemiacetal equilibria,
Table 226
Hydroxydiazines, tautomerism 429
Hydroxyleucine, structure 503
β-Hydroxy-β-methylglutaryl-CoA, see
HMG-CoA
Hydroxyproline, structure 503
5-Hydroxytryptamine (5-HT, serotonin)
structure 446
receptors, 446
biosynthesis 602
5-Hydroxytryptophan
decarboxylation to 5-hydroxytryptamine
602
structure 602
Hyoscyamine
base hydrolysis 376
biological activity of enantiomers 78
racemization 77, 375
stereochemistry and shape 117
as tropane alkaloid 370
Hypoxanthine, in purine metabolism 451
Hysocine, stereochemistry and shape 117
Ibuprofen
biological activity of enantiomers 79
metabolic racemization 377
nomenclature 13
synthesis 314
Idose
Fischer projection 104
structure and stereochemistry 465
Iduronic acid, in heparin 496
Imidazole
basicity 143, 433
Chichibabin reaction 437
hydrogen bonding 435
molecular structure 432
reactivity 432
structure 432
Imidazole ring, tautomerism 517
Imidazoles, tautomerism 433
Imines
from aldehydes and ketones 242–7
in aldolase mechanism 526
as carbonyl analogues 243, 369
basicity 138
formation, comparison with acetal
formation 243
formation, intramolecular 245
formation, mechanism 242
electronic structure 34
in enzyme binding 516
hydrolysis 243
reduction with complex metal hydrides 246
in reductive amination 598
in Strecker synthesis of amino acids 245
Imine–enamine tautomerism, in
transamination 599
Imino acid, proline 499
Indole
acidity 445
aldol-like reactions 445
alkylation 445
basicity 443
electrophilic substitution 444
Fischer synthesis 461
hydrogen exchange 443
in Mannich reactions 445
in Michael reactions 445
reactivity 443–6
systematic name 439
Indole-3-acetic acid, structure 447
Inductive effect
influence on acidity 125–7
influence on basicity 137
definition 37
in electrophilic aromatic substitution 310
from functional groups, Table 126
Inhibitors
aminoacyl-tRNA binding 558
enzyme, see enzyme inhibitors
transcription 558
translation 558
Initiation step, radical chain reaction 323
Inosine phosphate, in nucleotide biosynthesis
563
myo-Inositol, conformational isomers 70
Insulin 486
biosynthesis 507
bovine, structure 507
disulfide bridges 507
human, structure 507
porcine, structure 507
Intermediary metabolism, definition 573
Intermediates
definition 173
energy diagram 174
International Union of Pure and Applied
Chemistry, see IUPAC
Intramolecular aldol reaction, see aldol
reaction
Intramolecular Claisen reaction, see Claisen
reaction
Intramolecular electrophilic addition 300
Inulin, structure 484
Inversion
at nitrogen 74
in S N 2 reactions 183, 190
Invert sugar 231
Invertase 231
Ion 19
Ionic bonding, see bonding, ionic
Ionic reactions 167–71
Ionization
amino acids at pH 7 150
calculation 150
morphine 163
Ionization constant, water
K w 135
temperature dependence 146
Ionization potential 23
Irreversible reactions, of carbonyl group 223
Isoborneol, in synthesis of camphor 219
Isocitrate, in Krebs cycle 586
Isocitrate dehydrogenase, in Krebs cycle 389,
587
Isodihydrocarvone, interconversion with
dihydrocarvone 353
Isoelectric point pI
alanine, calculation 161
amino acids, calculation 160
definition 160
glutamic acid, calculation 161
lysine, calculation 161
morphine 163
Isoleucine, structure and pK a values 500
Isoliquiritigenin, synthesis by aldol reaction
306
Isomers
configurational see configurational isomers
conformational see conformational isomers
constitutional 56
geometric 83
optical see optical isomers
structural 56
Isomerase, in unsaturated fatty acid
metabolism 593
Isomerism, cis –trans 30, 40
Isomerization, of glucose 467
Isopenicillin N
in penicillin biosynthesis 376
as precursor of β-lactam antibiotics 537
Isopentenyl diphosphate, in terpenoid and
steroid biosynthesis 300
Isoquinoline
basicity 442
Bischler–Napieralski synthesis 459
Chichibabin reaction 443
nucleophilic substitution 443
reactivity 442
systematic name 439
Isoquinolone 443
Isothiazole
basicity 438
structure 432
Isotopic labelling
carboxylic acid derivatives 374