Quinine sulphate (neutral), 2 (C20 H24 N2 O2). H2 SO4 + 8 H2O.

2

(6) Solution in alcohol of 80 per cent. by vol.

[a]p 162.95.

=

(7) Solution in alcohol of 60 per cent. by vol.

(8)

Solution in hydrochloric acid:

1 mol. sulphate + 4 mols. H Cl + water.
Anhydrous salt. c = 2. [a]D

=

2

c = 2.

c = 2.

239.2.

Quinine sulphate (mono-acid), (C20 H24 N2 O2). H2SO4 + 7 H2 0.

Quinine disulphate (di-acid), (C20 H24 N2 O2) . 2 H, SO4 + 4 H2O.
Solution in water. c = 2 to 10.

2

For the rotation of this salt with 7 mols. H2O, see Chapter VII. Solutions in sulphuric acid:

I. 1 mol. quinine hydrate + 3 mols. H2SO4 + water to 100 cub. cent.

II. 1 mol. sulphate + 2 mols. H2 SO4 + water to 100 cub.

III. 1 mol. disulphate + 1 mol. H2 SO4 + water to 100 cub.

2

(16)

Cinchonidine hydrochloride, C20 H24 N2 O. H Cl + H2 O.

2

=

Solutions in hydrochloric acid: 1 HCl or 1 mol. alkaloid + cub. cent. c = 1 to 10. Salt Alkaloid [a]D Cinchonidine sulphate (neutral), 2 (24) Solution in water. c = 1.06.

(22)

(23)

= ―

2

(154.07 1.39 c).

(181.32 - 1.925 c).

(C20 H24 N2 O). H2SO4 + 6 H2 O.

Salt [a] 106-77.
Alkaloid [a]D

=

2

142.31.

2

Cinchonidine sulphate (mono-acid), (C20 H24 N2 O). H2 S 04 + 5 H2 O. (25) Solution in water. c = 2. Salt [a]D

Cinchonidine disulphate (di-acid), (C20 H24 N2 O). 2 H2SO4 + 2 H2, O. Solution in water. c = 1 to 7.

(105.96–1.0267 c + 0·03376 c2−0·00104 c3).

- (185·77-3·1557 c + 0·18158 c2 −0·00981 c3).

Quinidine or Conchinine (dextro-rotatory).

Quinidine hydrate, C20 H24 N2 O2 + 21⁄2 H2 0.

(28)

(29)

Solution in alcohol of 97 per cent. by vol. c = 1 to 3.
Hydrate [a]D = + (236-77

- 3.01 c).

Anhydride [a] =+ (269-57 - 3.90 c).

Quinidine hydrochloride, C20 H24 N2 O2. H Cl + H2 0.
Solution in water. c = 1 to 2.

(30)

(31)

Salt
Alkaloid

[a] = + (205.83 - 4.93 c).

[a]D +(240-45 - 6.60 c).

Solutions in hydrochloric acid: 1 mol. hydrochloride + 2 mols. H Cl, or 1 mol. alkaloid + 3 mols. H Cl + water to 100 cub. cent. c = 1 to 5.

(32)

(33)

Alkaloid [a] =+ (338 37 - 4.52 c).

Diquinidine sulphate, 2 C20 H24 N2 O2 . H2 S O4 + 2 H2O.

2

2

(34) Solution in water. c = 1. Salt. [a] + 179.54.

Alkaloid [a]

Solution in hydrochloric acid:

+ water.

=

= + 215.55.

1 mol. salt + 4 mols. H Cl

(35) Anhydrous salt. c = 2. [a]D = + 286.4.

Alkaloid [a]

= 329.8.

mol. salt + 5 mols. H2SO

Solution in sulphuric acid: 1

+ water.

(36) Anhydrous salt. c = 2. [a] = + 281.

Alkaloid [a] = + 323.

Quinidine sulphate, C20 H24 N2 O2 S O4 +

Alkaloid [a] = + (323·23 — 186 c).

Solution in sulphuric acid: 1 mol. disulphate + 2 mols. H2SO4 + water to 100 cub. cent. c = 1 to 10.

Solution in alcohol of 97 per cent. by vol. c = 0·5. c = 1. Mean. [a]D = + 226·36 225·96

Cinchonine hydrochloride, C20 H.24 N2 O . H Cl + 2 H2 O.

226.13.

Solutions in hydrochloric acid: 1 mol. hydrochloride + 2 mols. H Cl, or 1 mol. alkaloid + 3 mols. H Cl + water to 100 cub. cent. c = 1 to 7.

Hydrochloride [a] = + (214·0 1.72 c).

Alkaloid

[a]D = + (264.37

2.625 c).

Dicinchonine sulphate, 2 C20 H24 N2O. H2SO4 + 2 H2 0.

2

Solution in water. c = 1 to 2.

(46) Salt [a] = + (1703 0·855 c).

(47)

(48)

(49)

Alkaloid [a] = + (206-79 - 1.26 c).

Solution in sulphuric acid: 2 mols. dicinchonine sulphate + 5 mols. H2 SO4 + water to 100 cub. cent. or 3 mols. sulphuric acid to 1 mol. alkaloid. c = 0.5 to 6.

2

D

1.85 c).

Sulphate [a] = +(219·10
Alkaloids [a] = + (266-07 2.69 c).

For the rotatory powers of the other cinchona bases, see Chapter VII.

§ 104. Oudemans1 has determined the specific rotation [a] of anhydrous quinine and cinchonidine (both lavo-rotatory) in solution in absolute alcohol for different degrees of concentration (e grammes of substance in 100 cubic centimetres), and at different temperatures t, with the following results :

By employing a dilute alcohol as the solvent, the specific rctation of the cinchona alkaloids decreases with the amount of the dilution.

1 Oudemans: Liebig's Ann. 182, 46. The results obtained by Oudemans do not admit of strict comparison with those given by Hesse, as the former employed absolute, and the latter 97 per cent., alcohol.

Oudemans gives the following observations on this point made at a temperature of 17° Cent.

The following values, also given by Oudemans, for the specific rotation of the various salts, apply to solutions containing each 0.308 to 0.324 gramme (molecular weight of C20 H24 N2 O and C20 H24 N2 O2) of the particular alkaloid in 20 cubic centimetres of solution, or 1.54 to 1.62 grammes per 100 cubic centimetres. Temperature, 17° Cent.