Resins and resin combinations

Resin; Introduction, Properties, and Classification

1. RESINS AND RESINS
COMBINATION
Presented by
O.P. Verma
Associate Professor
GoelInstitute of Pharmacy and Sciences
Lucknow, Uttar Pradesh, India

2. RESINS AND RESINS
COMBINATION
Theterm‘resin’isappliedtomoreorless
solid,amorphous productsofcomplex
chemicalnature.
Theseareamorphousmixturesofessential
oils,oxygenatedproductsofterpenesand
carboxylicacids

3. Resinsandrelatedresinousproducts
areproducedinplantsduringnormal
growthorsecretedasaresultofinjury
totheplants
Theyareusuallyoccurinschizogenous
orschizolysigenouscavitiesorducts

4. GENERAL PROPERTIES
Physical characters –
Allresinsareheavierthanwater,theyare
usuallyamorphous,hard,andbrittlesolids.
Theyareinsolubleinwaterandusually
insolubleinpetroleumetherbutdissolvemore
orlesscompletelyinalcohol,chloroformand
ether.

5. Chemically,resinsarecomplexmixturesof
resinacids,resinalcohols(resinols),resin
phenols (resinotannols),estersand
chemicallyinertcompounds knownas
resenes.
Manyresins,whenboiledwithalkaliesyield
soaps

6. Bytheactionofheattheysoftenyielding
clear,adhesivefluids,Resinsburnwitha
characteristic,smokyflame.
Resinsareoftenassociatedwithvolatile
oils(oleoresins),withgums(gum-resins)
orwithoilandgum(oleo-gum-resins).
Resinsmayalsobecombinedina
glycosidalmannerwithsugars.

7. CHEMICALPROPERTY
Chemicallyresinsarenotpuresubstances
butcomplexmixturesofseveralresinous
substancesasresinacids,resinalcohols,
resinesters,andneutralresins.
Resinsdonotcontainnitrogenelements
(Nonnitrogenouscompounds)

8. CLASSIFICATIONOFRESINS
Resinsareclassifiedinthreedifferent
ways:
1.Taxonomical classification, i.e.
accordingtobotanicalorigin,e.g.
Berberidaceaeresins.
2.Classification according to
predominatingchemicalconstituent;
e.g.acidresins,reseneresins,glycosidal
resins;etc.

9. 3.Resinsmaybeclassifiedaccording
totheportionofthemain
constituentsoftheresinorresin
combination;e.g.resins,oleoresins,
oleo-gum-resins,balsams.

10. CLASSIFICATION OF RESINS
1. Acid resins –
Heretheresinsoccuralongwiththeiracids.
Examples–
Colophony–Abieticacid
Sandrac-Sandracolicacid
Myrrh-Commiphoricacid
Copaiba-Copaivicacid

11. 2. Ester resins –
Thisgroupcontainsestersasthechief
constituentsoftheresins-
Examples
BenzoinandStorax,
Benzoincontainsbenzylbenzoate,
Storaxcontainscinnamylcinnamate

12. 3.Resin alcohols –
Theyoccursasinfreestateorasesters
,
Examples–
Balsamofperuwithperruresinotannol
Guaiaccumresinwithguaicresinol

13. 4.Glucoresins
Resinssometimesgetcombinedwithsugarsbyglycosylation
andproduceglucoresins.Glycoresinscanbehydrolysedby
acidichydrolysistotheglyconeandaglycone.
5.ResinEsters
Resinestersaretheestersoftheresinacidsortheother
aromaticacidslikebenzoic,cinnamic,salicylicacids,etc.
Theyaresometimesconvertedtotheirfreeacidsbythe
treatmentwithcausticalkali.Dragon’sbloodandbenzoinare
thecommonresinestercontainingdrugs.

14. Theyarealsofurtherclassifiedinto–
Resins:colophony,cannabis.
Oleoresins:copaiba,ginger.
Oleo-gum-resins:asafoetida,myrrh.
Balsams:balsamofTolu,balsamofPeru.
Glycoresins:jalap
Resenes:Asafoetida,colophony

15. BALSAMS
Balsamsareresinousmixturesthatcontain
largeproportionsofcinnamicacid,benzoic
acidorbothorestersoftheseacids.
Theterm“balsam”isoftenwronglyappliedto
oleoresinsandshouldbereservedforsuch
substancesasbalsamofPeru,balsamofTolu
andstorax,whichcontainahighproportionof
aromaticbalsamicacids.

16. PREPARATION OF RESINS
Twogeneralclassesofresinoussubstancesare
recognizedandthisclassificationisbasedon
themethodusedinpreparingthem:
1.Naturalresins
Occurasexudatesfromplants,produced
normallyorasresultofpathogenicConditions
Examplebyartificialpuncturese.g.mastic;or
deepcutsinthewoodoftheplante.g.
turpentine,orbyhammeringandscorching,
e.g.balsamofPeru.

17. 2. Prepared resins;
Areobtainedbydifferentmethods.Thedrug
containingresinsispowderedandextracted
withalcoholtillexhaustion.
TheConcentratedalcoholicextractiseither
evaporated,orpouredintowaterandthe
precipitatedresiniscollected,washedand
carefullydried.

18. Inthepreparationofoleoresins;ether
oracetonehavinglowerboilingpoint
areused.
Thevolatileoilportionisremoved
throughdistillation.
Whentheresinoccursassociatedwith
gum(gum-resins),theresinis
extractedwithalcoholleavingthegum
insoluble.

19. Thank you