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a secondary alcohol obtained from ordinary camphor by reduc-
tion.

CyHieCO -h 2H = CgHieCHOH
Camphor Borneol-camphor



12

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178 CHEMICAL PHABMACOLOGY

Camphor is oxidized in the body to camphorol,
CioHieO -> CioHieO.OH

This then combines with glycuronic acid and is excreted as
the glycnronate

C10H15O.OH + C«Hio07 = CioHuO O.CeHyOe + H,0

The camphors are used in medicine chiefly in liniments and
for stimulation of the respiratory and circulatory centres, as
well as the heart muscle in threatening collapse. Externally as
a liniment, camphor irritates the skin and dilates the vessels.
It is used therefore as a rubifacient. It has a mild antiseptic
action and is used to keep away insects. Camphor vapor is a
mild paralyzer of all undifferentiated protoplasm. When taken
by mouth it lias a warm bitter taste and carminative action,
much like the volatile oils. Large doses may cause nausea and
vomiting. If large doses are taken it may be absorbed and if so
has a definite stimulant action on the central nervous system,
much like the volatile oils. 10 cc. per kilo of body weight of a
20 per cent, solution -of camphor in olive oil given to a rabbit will
produce peculiar bucking spasms in which the animal may turn
a sommersault backwards.

Menthol. — CioHmO. Menthol is a secondary alcohol de-
rived from peppermint-mentha piperita. It occurs in crystals or
prisms, the solubility of which is the same as the volatile oils.
The dose is about 1 grain, and it is used as an antiseptic, analgesic
and stimulant.

H3C CH3

\y

C— H

I
C— H

Hj=c c— h oh

_l I

H2 G CH2

CCH,

I
H

Menthol



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THYMOL 179

Thymol is a phenol from the oil of thyme. It occurs in large
translucent rhombic prisms, its solubilities in general being the
same as the othet stearoptenes. It is used especially in the
treatment of hookworm disease, also as an antiseptic and anti-
pyretic:

Thjrmolis lodidum. — Aristol-thymol iodide is a condensation
product consisting of two molecules of thymol containing iodine
in the phenolic groups. It is a reddish yellow powder and is
used for the same purposes as iodoform, i,e, antiseptic.

Menthol has many of the actions of camphor. It is much used
as a nasal spray, 1 per cent, menthol in light liquid petrolatum,
with volatile oils. When rubbed on the skin it dilates the
vessels as camphor does, but it stimulates the "cold" nerves,
and there is a sensation of numbness of partial anesthesia due
to a paralysis of the sensory nerves, after primary stimula-
tion. For this reason it is sometimes used with benefit in neiuttl-
gias. It is excreted in combination with glycuronic acid as
menthol-glycuronic acid.

CII3 CHs CHa

I I I

c c . c

• /v /v y\

HC CH HC C C CH

II I il I I II

HC COH HC COI IOC CH

x/- \/' \/

c c c

■ I .1 I

CsHy C3H7 C3H7

Thymol Dithymol-diiodide (Thymolis iodidum).

1. Note odor and test solubility in water, alcohol, ether and
in fixed oils, of camphor, menthol or thymol.

2. Triturate a small piece of camphor with thymol, chloral,
or menthol.

3. Repeat this with any of the stearoptenes and phenacetin,
acetai^ilid or antipyrin.



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180



CHEMICAL PHABlfACOLOaT



Carvacrol is an isomer of thymol. It has the formula

CH,



\0H



I
CH

I

0X13 0X13

Carvacrol.

It occurs with thymol in many labiate plants, particularly in
the species origanum and in the oil of thyme it sometimes re-
places all of the thymol. It has the same pharmacological ac-
tions as thymol and can be used instead of it in hookworm disease.
Because of the great demand for thymol in the treatment of
hookworm disease its supply is inadequate. Attempts to produce
thymol synthetically have not been successful from a commercial
standpoint. Carvacrol was first prepared synthetically by Sch-
weitzer (J. Prakt. Chem., 1841, XXIV, 257) and recent work
shows that it may be prepared synthetically from the commercial
point of view. (Hixon and McKee, Journal of Industrial and
Engineering Chemistry, 1918, X, 982).

Besides its use in the treatment of hookworm disease— thymol
is occasionally used as a parasiticide. It has been used in ring-
worm with good results. 5 to 10 per cent, solution in alcohol
being applied directly to the growth. Thymol is excreted com-
bined with glycuronic and sulphuric acids.

XX. RESINS, OLEORESINS, GUM RESINS, AND BALSAMS

Resins are an ill-defined group of amorphous, brittle oxidized
hydrocarbons. They are not pure chemical bodies, but mix-
tures. They are allied to, and probably derived from the vola-
tile oils, and occur as exudations of plants excreted in the course



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OLEORESINS 181

of metabolism. Most natural resins consist of a mixture of
peculiar resin acids, which dissolve in alkalies forming resin
soaps. These soaps have detergent properties similar to the
ordinary soaps, and because of their great water-holding power
have been used to adulterate ordinary soaps. The saponifi-
cation value aids in the identification of resins.

Resins are characterized by being insoluble in water and pe-
troleum ether, soluble in alcohol and volatile oils, and when broken
by presenting a smooth shining siuface, are amorphous, sticky
and fusible and burn with a smoky flame. They are almost
invariably a mixture of different substances. When resins occur
with volatile oils, they are called oleoresins. When mixed With
gums they are gum resins. Balsams are resins or oleoresins that
contain benzoic or cinnamic acids. The term resin is also used
in chemistry to include such bodies as are formed when a mixture
of alcohol and potassium hydrate are allowed to stand. The
dark colored material that forms and is soluble in the alcohol is
designated as a resin.

The most important resins are those of copaiba, jalap, podo-
phyllum, scammony, guaiacum-wood, gamboge, asafoetida, and
caoutchouc. Amber is a fossil resin and consists of two resin
acids, and a volatile oil. Caoutchouc is prepared from a number
of tropical euphorbiacese, apocinacese, etc. When purified its
formula is (C6H8)n. On distillation it will polymerize spontan-
eously to caoutchouc and also to dipentene. It takes up sul-
phur readily when treated with sulphur chloride (S2CI2) in CS2
and the product is vulcanized rubber.

1. Test the solubility of resin in water, alcohol; ether, oil of
turpentine, dilute boiling NaOH and H2SO4.

2. Mix an alcoholic solution of shellac with water; with dilute
alcohol.

3. Mix an alcoholic solution of shellac or resin with mucilage
of acacia. Shake and let stand.

OLEORESINS

These are solutions of resins in ethereal oils. The chief oleo-
resins are aspidimn, capsicum, cubeb, lupulin, ginger, and black
pepper. Aspidium is the most important of the group, and is
used in the treatment of tapeworm. It is the principal remedy for
this purpose.



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182 CHEMICAL PHARMACOLOGY

Acetone is the solvent used in the preparation of the oleoresins.
It is less expensive and less explosive than ether, and is an ex-
cellent solvent.

1. Evaporate an alcoholic solution of gum turpentine in a
small porcelain dish. Note the odor, and the characteristic
residue. Explain.

2. Compare the appearance of the oleoresins and the resins.
To what is the physical difiference due?

3. Place about 25 grams of ginger, pepper, or powdered as-
pidium in a Soxhlet apparatus and extract with acetone. When
the extraction is complete distil ofif the solvent and examine the
residue-oleoresin. Study the solubility in cotton-seed oil, muci-
lage and water. Shake.

GUM RESINS

Gum resins are mixtures of resins or oleoresins with gums.
Asafoetida, ammoniac, myrrh, gamboge and scammony are the
most important.

Triturate a Imnp of asafoetida in a mortar with water. Note
the odor and the character of the mixture. Test the influence of
the addition of alcohol. This drug is used in neurasthenic and
hysterical conditions. The influence of it, if it has any, is due to
the odor, i.e. psychic effect.

Boil some of the gum resin with a little H2SO4. Neutralize and
filter. Test the filtrate with Fehling's solution. Place 5 grams
of gum in a distilling flask, add 25 cc. concentrated HCl and distil
from a sand bath. Let the distillate drop on a piece of filter paper
moistened with aniline acetate. A red color indicates the pres-
ence of a pentose, which is converted into furfural by the following
reaction.

C5H10O6 - 3H2O -^ C4H3O.CHO
Sugar indicates the presence of a gum. Explain the presence and
kind of sugar.

BALSAMS

Balsams are resins or oleoresins that contain benzoic or cinna-
mic acid. The most important are those of peru, tolu, and storax
or styrax. Balsam of copaiba contains neither benzoic or cin-
namic acid and is, therefore, not a balsam. On the other hand
cranberries and other berries of the Ericacese, contain benzoic
acid but contain no resin.



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GLUCOSIDES 183

XXI. GLUCOSIDES OR COMPOUND SUGARS

Glucosides are substances which on hydrolysis yield glucose
or a related sugar, and another substance. In many cases the
composition of the other substance is unknown; usually it is an
aromatic body. The sugar may be rhamnose, galactose, ribose,
arabinose, or any disaccharide that yields a sugar related to glu-
cose. Some glucosides contain only C, H, and O, a few have N,
in addition, and one or two contain sulphur. The part remaining
after the sugar is split off may be alkaloid, e.g. solanine, in which
case the term alkaloidal glucoside would be appropriate. Vege-
table bases however are rarely found in glucosidic combination.
Some of the glucosides are highly toxic, others inert. The
characteristic feature is the yield of glucose or related sugar and
another substance which is not a carbohydrate (different from
gums, starches, sugars polyoses). They are incompatible with
free acids, or ferments, since they are decomposed by these agents.
Some are also decomposed by alkalies. Many Jiave ferments
associated with them in the plant, which are liberated on crush-
ing, and in a water solution hydrolyse the glucoside.

PENTOSroES, GALACTOSIDES, ETC.

Some writers restrict the term glucoside to compounds yielding
hexose sugars, and designate those yielding pentose sugars, as
pentosides, while those that give galactose on hydrolysis are galac-
tosides. This is a refinement in classification that may or may
not be advisable^ Pentosanes, hexosanes, etc. differ from pento-
sides and glucosides in being polyoses and not compounds. On
hydrolysis pentosanes give pentoses only, hexosanes such as cel-
lulose give hexoses only. Other writers taking a wider view
include under glucosides, such polyoses as saccharose, raffinose,
and gentianose. This is because their combination is ether-like
and, similar chemically to artificial glucosides.

CONSTITUTION OF THE GLUCOSIDES

Chemically, glucosides are ether-like combinations of glucose
with alcohols, acids, phenols, etc. (see table of composition) . Their
constitution is analogous in some respects to acetals or aldehyde
alcohols:



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184



CHEMICAL PHARMACOLOOT
H



R.— C = O

Aldehyde



H OCH,
+ H ;0CH3



Alcohol



H



OCH3



R.— C^

^0CH3

Acetal.

Since they contain no free aldehyde groups they will not form
osazones and will not reduce Fehling's solution until hydrolysed.

Some glucosides have been prepared synthetically, and the
composition of the synthetic product, gives one an idea of gluco-
sidic composition in general. The best known synthetic glucoside
is the combination of methyl alcohol and glucose. This is pre-
pared by treating a concentrated solution of d. glucose in methyl
alcohol with gaseous hydrochloric acid. Two isomeric products
are formed. (1) An alpha, glucoside which is dextro-rotatory
+ 157° and dissolves in 200 parts of alcohol and melts at 165**,
and beta, glucoside which is levo-rotatory — 33° and is soluble in
67 parts of alcohol and melts at 104°C. They can be separated
by their different solubilities.

The formulas assigned to these different glucosides are:



(«)
(7)

(b)
(a)





-.— C— OCH,
a-glucoside



CHaO— C H

|8-glucoside



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GLUCOSIDES 185

The a, and & glucosides are formed simultaneously, the o,
predominating. Equilibrium is established when the mixture
contains about 77 per cent, o, and about 23 per cent, of the 8
isomeride. On standing the jS form is slowly converted into
the more stable (a) form.

The basis for the assumption of these formulas are:

(I) A single molecule of alcohol reacts with a single mole-
. cule of glucose, with the elimination a molecule of water. One of
- the secondary alcoholic radicals of the sugar must therefore be

involved.

(II) These glucosides are readily hydrolysed into their con-
stituents. This indicates that the alcohol radical is joined to
the sugar, by means of the oxygen, since if the union were by
means of the carbon atoms direct, they would not be so easily
hydrolysed. (Compare the action and fate of alcohol and ether
in the body.)

(III) The elimination of water is from the (a, and 7) positions,
since other compounds containing R — CHOH.CO. do not yield
glucosides. The (a) group does not react therefore, and in favor
of the (7) position is the fact that other such combinations are
known; and only combinations containing the (7) group form
glucosides.

From the above, it is seen that there are at least two classes of
glucosides, the alpha and the beta. Maltase splits or hydrolyses
the a group, while emulsin hydrolyses the jS group.

Burquelot's biological method of investigating plants for glu-
cosides, consists in determining the optical rotation and cupric
reducing power of extracts before and after incubation with
emulsin. A change in these properties indicates the presentee
of jS glucosides, and gives a rough estimate of the amount.

The following table illustrates the hydrolysing action of these
enzymes on the different sugars and glucosides.



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186



CHEMICAL PHABMACOLOGT



I. '


II.




III.


Invertin


Maltase


Emulsin


Saccharose


Maltose


Aesculin


Raffinose
Gentianose


Methyl-d-glucoside-a Amygdalin
Ethyl-d-glucoside-a Androsin
Benzyl glycoside Arbutin
Glycerine glucoside-a Aucubin
Amygdalin Benzyl-glucoside
Trehalose Coniferin




Methyl-d-f ructoside Daphnin
Dhurrin






Gentiopicrin
Glyceryl-glucoside






synigrin
Helicin






Incaratrin






Indican






Lactose






Melatin






Methyl-d-galactoside 8
Methyl-d-glucoside 6.
Oleuropein .
Picein






Pninasin






Prnlaurasin




CHaOH






H— C— OH




(7)


H— (>-0H






m


HO— C— H






(a)


H— C— OH








C =


+ H


OCH,




Methyl a
H


Jcohol




Glucose







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187



O + HaO



H

Glucoside
By treatment with methyl-iodide and silver oxide under proper
conditions, alpha, and beta pentamethyl glucosides may be pre-
pared with the formula:

Me.OC— H




CH20Me
(a) pentamethyl glucoside.
These esters are not acted on by enzymes, but when they are
hydrolysed by acids, alpha and beta, tetra-methyl glucosides
are formed:

HO— C^H




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188



CHEMICAL PHARMACOLOGY



These rapidly change into the same form with constant rotatory-
power. The alpha tetra methyl glucoside is not fermentable,
but the beta form can be hydrolysed by emnlsin. This enzyme
is especially wide in its action and so far as is known acts only
on beta glucosides.

COMPOSITION OF NATURAL GLUCOSIDES

The natural glucosides are generally colorless crystalline solids
with bitter taste, and levo-rotatory optical power. All natural
glucosides so far isolated are of the beta form. They can all
be hydrolysed by acids though some are very resistant. Emulsin
will hydrolyse a large number of them. Van Rijn (Die Glu-
coside) classifies glucosides according to the plants from which
they are derived. A complete chemical classification cannot be
given, but according to the non-sugar products of hydrolysis,
Armstrong (The simple Carbohydrates and Glucosides) gives
the following table :



Glucosides




M.p.


Products of hydrolysis


Arbutin


CiiHieOT
CseHssOii

C2lH2409

CeoHeoOtT
C24H26OU
C11H18O7

CsiHjiOio

CieHifOs

CuHhOt
CitHmOb

CoHstOixN
OuHitOtN
CuHieOr
CioUitObN

Cl4Hl706N

C14H17O6N
CisHibOt
Ci4Hi70«N
Ci»Ht60ioN


187'
240*
175"
25r
208"
176'
170*
170*

185"
180*
201"
191*

200''

141"
122"
147"
195"
151"
160'


Phenols
Glucose + hydroquinone


Baptisin


Rhamnose -f- baptigenin


Glycyphyllin

Hesperidin


Rhamnose + phloretin

Rhamnose -|- 2 glucose -|- hesperetin


Iridin


Glucose + irigenin


Methyl arbutin

Naringin


GHucose + hydroquinone methyl ether
Rhamnose -H glucose + narigenin


Phloridzin


Glucose + phloretin


Coniferin


Alcohols
Glucose "t* coniferyl alcohol


Populin

Salicin


Glucose + saligenin + bensoic acid
Glucose -|- saligenin


Syringin


Glucose + syringenin


Amygdalin


Aldehydes
2 Glucose -f- d-mandelonitrile


Dhurrin


Glucose + p-oxymandelonitrile


HeUcin

Tjinaniarin . r


Glucose + salicylaldehyde
Glucose -|- acetonecyanhydrin


Prulaurasin

Prunasin

Salinigrin

Sambunigrin

Vicianin


Glucose + racemic mandelonitrile

Glucose + d-mandelonitrile

Glucose + m-oxybensaldehyde

Glucose + l-mandelonitrile

Glucose + arabinose + d-mandelonitrile



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GLtrCOSIDES



189



Glucoside




M.p.


Products of hydrolysis


Convolvulin

Gaultherin


C64H»«Ot7

Ci4HuOt

C44H6«Ou
C40H6«Ol»

CiiHuOt
Ci6HuO»
CuHigOio
CstHssOu
CuHieOt

CfiHsoOa
CtiHaoOio
C««HjiOi4

CteHxtOu

CssHteOu

CtiHioOu

CtiHxoOit

CtiHtoOit

CMH«iOieN

CtiHtoOu

CmHsoOu

Ct7Hs«Ol6

CtiHttOit
CrHjoOie

CS4H4SOSO

Ci4HisO.NS,K
CMH4fOi,N» Sx

CioHuObNSxK

CuHi90.
CxoHitO*
Ci»HmOii
CxiHmOu
CsiHieOu

C»4H640ll
Ct6HuOl4
C«4H9tOs8

CnHxoO*

Ci,H,.O.N

CuHnOeN

Ct7H»Ol4
CsoH4808

C15H14O7
CioHu06N»


150*

lOO"
131'

205*
200"
320*
218**
210*

228*
202*
258*

228*
218"

242-
217«

247"
183«
184'
245^

138"
126"

144"
190**
217"
145"
274"
225"
191'
162"
100"
201"


Acids
Glucose + rhodeose + convolvulinolic
acid
Glucose + methylsalicylate


Jalapin


Glucose -|- jalapinolic acid


Strophanthin

.Alsculin


Oxycumarin Derivatives
Glucose -|~ aesculetin


Daphnin


Glucose -f* daDhnetin


Fraxin


Glucose + fraxetin


Scopolin


3 Glucose -{- scopoletin


SkiTATKX''*


Glucose ~|~ skiniinetin


Prangxjlin


Oxyanthraquinone derivatives
Rbamnose -1* emodin


Polygonin


Glucose -{- emodin


Ruberythric acid. . .
Apiin


Glucose + alizarin

Oxyflavone derivatives
Apiose + apigenin
Rhamnose -^ fisetin


Fustin


Gossypitrin

Incarnatrin

laoqueroitrin

Lotusin


Glucose + gossypetin

Glucose-quercetin

Glucose + quercetin

2 Glucose + HON + lotoflavin


Queroimeritrin

Queroitrin


Glucose + quercetin

Rhamnose + quercetin

Glucose -{- rhamnose 4- quercetin


Rutin


Serotin.


Glucose + quercetin

Rhamnose -|- glucose -h sophoretin


Sophorin


Xanthorhaminin . . .

Glucropaolin

Sinalbin


2 Rhamnose + galactose + rhamnetin
Mustard oils
Glucose + benzyl isothiocyanate
Glucose + sinapin acid sulphate + acrinyl
isothiocyanate
Glucose + allyl + isothiocj^anate +


Sinigrin


Aucubin


KHSO4

Various
Glucose + aucubigenin


Barbaloin


d-arabinose -\- aloemodin ■


Calmatambin

Datisoein


Glucose + calmatambetin
Rhamnose -i~ datiscetin


Digitalin


Glucose -|- digitalose -{- digitaligenin


Oi gitoxin .,,,.- ., ,


2 Digitoxose + digitoxigenin


Gentiin


Glucose + xylose + gentienin


Digitonin


Glucose -|- galactose •{■ digitogenin


Gentiopicrin

Gynooardin

Indioan


Glucose + gentiogenin
Glucose + HCN + C.H804
Glucose + indoxyl


Kampheritrin

Quinovin


2 Rhamnose + kampherol
Quinovose + quinovalic acid


Saponarin


Glucose -^ saponaretin


Baponins. ..... r ... .


Glucose -{- galactose -|- sapogenins


Vernin


d-Ribose -|- guanine







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190 CHEBHCAL PHARMACOLOGY

An examination of this table will show that there is little rela-
tion between the known chemistry and pharmacological action.
As a rulei however, the combination of sugar with another radical
increases the action of that radical. This is well illustrated in the
action of chloral, which, when combined with glucose to form
chloralose, is increased and becomes more like morphine in action.
Relatively few glucosides however are used in medicine.

The chief glucosidoclastic enzymes are:

Enzymes Hydrolyses •

Emulsin Many natural glucosides

Synthetical /^glucosides

Prunase Prunasin and many other

natural glucosides

Amygdalase Amygdalin

Gaultherase Gaultherin

Linase Linamarin

Myrosin Sinigrin and sulphur glucosides

Rhanmase Xanthorhammin

Emulsin from almonds, hydrolyses, sesculin, amygdalin, andro-
sin, arbutin, aucubin, bankankosin, calmatambin, coniferin,
daphnin, dhurrin, gentiopicrin, helicin, incarnatrin, indican,
melatin, oleuropein, picein, prulaurasin, prunasin, salicin, sam-
bungrin, sjmingin, taxicatin, verbenalin, etc.

The most important glucosides in medicine are:



Amygdalin


Helleborein


Arbutin


Jalapin


.^culin


Phloridzin


Coniferin


Salicin


Convallarmarin


Saponin


Convallarin


Strophanthin


Digitalin


Scillin


Digitoxin


Sinigrin


Digitophyllin


Sinalbin


Digitalein




Digitonin




Aloin





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GLUCOSIDES 191

Glychyrrhizin was formerly included in this group, but it is not
a glucoside.

Another classification, of glucosides based on the chemical
groups found in the above is:

1. Ethylene derivatives.

2. Benzene derivatives.

3. Styrolene derivatives.

4. Anthracene derivatives.

The chief representatives of this classification are:
1. Ethylene Derivatives. — Sinigrin CioHieNSaKOg + H2O is
the glucoside of black pepper, mustard, horse radish and trops&-
olum seeds. It is the potassium salt of myronic acid. On
hydrolysis it gives allyl mustard oil, dextrose, and potassium
bisulphate

0— SO2— OK

(>-&— CeHuOs + H2O -> CeHisOe + CgHsNCS + KHSO4

I

N— C3H5

Sinalbin C30H42N2S2O16, is the corresponding glucoside found
in white pepper. On hydrolysis it yields mustard oil, glucose,
and sinapin sulphate, which is a compound of choline and sina-
pinic acid and sulphuric acid: ,^

0— SO2OC16H24O6

I

C— SCeHnOs + H2O ->

I

N— CH2.C6H4.OH C7H7O.NCS

Sinalbin Sinalbin mustard oil

OH



+ CH3 OCH3 0H\

\

(CH,)3^N

I /

Sinapin CH : CH - CO.C2H4O



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192



CHEMICAL PHARMACOLOGY



Jalapin CsiHeeOie is the active principle of scammony, has
been assigned the formula



CH3



C2H



2-n.6



\



CH.CHOH.(CioH2o)COOH



Its decompositions are not definitely known.

Jalapin and Scammonium are identical. This glucosideis
the active principle of scammony (convolvulus scainmonia)
and Ipomoea orizabensis. It has the empiric formula CsiH^eOie
and when boiled with dilute acids yields Jalapinolic acid and
glucose:



CHa



C34HB6O16 + H2O =



C2H6



\



CH.CHOH.(CioH2o)COOH



+ 3C«Hi20«



2. Benzene Derivatives. — Arhutin Ci2Hi607 is the glucoside
found in bearberry (uva ursi). The leaves are used in medicine
and have a diuretic and antiseptic action. The antiseptic action
is due to the hydroquinone liberated. .



OH



OH



+ H2O



O.CeHuOs

Arbutin



+ C6H12O6



OH
Hydroquinone Glucose



The hydroquinone due to its oxidation imparts a dark color
to the urine.

Amygdalin is one of the best known glucosides and is found in
bitter almond. After hydrolysis with dilute acids, or ferments,
the presence of glucose may be shown with Eehling's solution.



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PHLORIDZIN 193

Benzaldehyde may be detected by its odor. The presence
of HCN may be shown by its precipitate with AgNOs or by the
Prussian-blue test. When the almond is ground with water,
at a temperature below 45°C. the enzyme emulsion contained in
the almond will hydrolyse the glucoside;

.0
C20H27NOU + 2H20= 2C6H12O6 + CeHBC^ + HCN •

Amygdalin Benzaldehyde.



The physiological action of the drug is due mainly to the HCN,
that is liberated in the intestine. Amygdalin is thought to be
a derivative of the nitrile of mandelic acid:



.CN
CeHsCHv yCi2H2iOio



Online LibraryHugh McGuiganAn introduction to chemical pharmacology: pharmacodynamics in relation to ... → online text (page 14 of 30)