1. General studies of the peptide bond 1.1 The peptide(O=C-N-H) bond was found to be shorter than the C-N bond in a simple amine and atoms attached are coplanar. 1.1.1 This was revealed by X-ray diffraction studies of amino acids and of simple dipeptides and tripeptides. 1.1.2 The peptide (amide) bond was found to be about 1.32 A (C-N single bond, 1.49; C= double bond, 1.27), thus having partial double bond feature (should be rigid and unable to rotate freely)
20.1 () Carboxylic aci id anhydrides bear two acyl groups on oxygen, as in RCOCR. They are named as derivatives of carboxylic acids. Q CH:CH2CHCOH CH,CH,CHCOCCHCH_CH3 C6H C. C. 2-Phenylbutanoic acid 2-Phenylbutanoic anhydride (c) Butyl 2-phenylbutanoate is the butyl ester of 2-phenylbutanoic acid. CH,CH,CHCOCH,CH,CH2CH
SOLUTIONS TO TEXT PROBLEMS 24.(b) A benzyl group(C., CH2) is ortho to the phenolic hydroxyl group in o-benzylphenol. OH CH2C.Hs (c)Naphthalene is numbered as shown. 3-Nitro-I-naphth has a hydroxyl group at C-1 and a nitro group
The triacylglycerol shown in text Figure 26.2a, with an oleyl group at C-2 of the glycerol unit and two ste earyl groups at C-I and C-3, yields stearic and oleic acids in a 2 I molar ratio on hydrolysis. A constitutionally isomeric structure in which the oleyl group is attached to C-1 of glycerol would yield the same hydrolysis products