Background technology
Chitin is one of natural high moleculer eompound the abundantest on the earth, and its year biosynthesizing amount is estimated to reach 10,000,000,000 tons more than, can be equal to mutually with cellulosic annual production completely.Great deal of research results shows, chitin and derivative thereof with its unique crop mechanism be used for agricultural plants pathogenic bacteria growth resistance preparation, crop disease-resistant lures agent alive, nematocides, seed treatment agent, fertilizer and soil improvement agent, fruit and vegetable fresh-keeping agent, food preservatives etc., it is the valuable source that non-polluted farm product is produced, simultaneously because of the antisepsis and anti-inflammation that it had and the effect of repair cell, it also obtains certain application in pharmaceutical industries.Chitosan (CTS; comprise oligose (oligochitosan) or high glycan) be the product that obtains behind the chitin deacetylation; there is a large amount of free amine groups to exist in the molecular structure; improve greatly than chitinous solubility property, have broad application prospects at agricultural, medicine, food, makeup and environmental protection aspects.But chitosan (CTS) is dissolvable in water in the acidic solution, can not be directly water-soluble, and meet sour facile hydrolysis viscosity is reduced, the film-forming properties variation.
Whitfield's ointment (SA) has plant regulates the promoter action and the germicidal action of growing, and plays bactericidal antiphlogistic, antipyretic effect in medicine, and its effect is similar to acetylsalicylic acid.But Whitfield's ointment (SA) has very strong pungency, can not directly take orally, takes for a long time and can bring in various degree gastrointestinal stimulation effect to the patient, even cause gastric perforation.
Summary of the invention
The object of the present invention is to provide a kind of 2-chitosan Whitfield's ointment graft compound and preparation method thereof, the graft compound of formation makes that the advantage of the two is brought into play, inferior position is suppressed.
For reaching above-mentioned purpose, the present invention adopts following technical scheme: 2-chitosan Whitfield's ointment graft compound, and its structural formula is:
Wherein, n=1-5000.
2-chitosan Whitfield's ointment graft compound preparation method, with chitosan (in monosaccharide units) and Whitfield's ointment by weight 10: 1-1: 2 add in the reactors, add the doubly dispersion agent of (W/V) of charging capacity 3-50, separate obtaining behind the 0-100 ℃ of reaction 1-3hr.
Dispersion agent is alcohol, ether, alcohol-benzene mixed solvent or aprotic polar solvent.
Chitosan and Whitfield's ointment be stirring reaction under 30-80 ℃ of temperature, the reactant behind the recovery solvent is done solvent refluxing with ethanol extract or wash to not containing free salicylic acid, gets 2-chitosan Whitfield's ointment graft compound.
2-chitosan Whitfield's ointment graft compound preparation method, with chitosan and Whitfield's ointment in 10-25 ℃ of solid state grinding reaction 1-3hr, solid substance after the grinding is at 50 ℃ of-100 ℃ of following thermal dehydrations or use the entrainment agent component distillation, product after the dehydration is done solvent refluxing with ethanol and is extracted or wash to not containing free salicylic acid, gets 2-chitosan Whitfield's ointment graft compound.
The component distillation entrainment agent is ethanol, benzene or ethanol-benzol mixture.
Reaction formula is as follows:
The present invention with chitosan (CTS) and Whitfield's ointment (SA) and derivatives graft thereof, prepares the 2-chitosan Whitfield's ointment graft compound of different percentage of grafting (20%-80%), different molecular weight (support C TS glucosamine unit is from 1-5000) with chemical synthesis.Because of the complementary effect, its performance is improved greatly, net effect obviously improves: aspect medical, chitosan (CTS) is fit to the chemically modified of defectiveness medicine or the template or the carrier of conduct preparation polymer drug, the medicine that contains Whitfield's ointment (SA) class composition after chitosan (CTS) is modified, its drug effect can be strengthened because of the physiologically active of chitosan self, stimulation to stomach mucous membrane can reduce significantly, chitosan (CTS) itself has cytothesis and refresh function again, can promote wound healing, its pharmacological action and the complementation of salicylic acid medicine, the effect that can improve related drugs; The agricultural aspect, the macromolecular compound that Whitfield's ointment (SA) and chitosan (CTS) grafting form, plant absorbing is used and be beneficial to its water-soluble raising more conveniently, and is more obvious than the effect of independent use; Chitosan (CTS) has stronger complexing action to multiple metal ion, combine complexing position, back increases with Whitfield's ointment (SA), complexing selectivity to some metal ions improves, can form more stable complex compound with multiple complexing of metal ion, be applicable to heavy metal ion detoxifcation, toxin expelling, tap water purification, Industrial Wastewater Treatment etc.
Among the present invention, chitosan can be oligose (oligochitosan) or high glycan, and average percentage of grafting is 10%-80%, and the percentage of grafting of oligochitosan can reach 100%.
The present invention prepares the percentage of grafting of product and measures: measure free Whitfield's ointment in the phegma with nonaqueous titrations, calculate and be connected in the chitosan molecule salicylic quantity on the glucosyl residue, obtain percentage of grafting; Or, try to achieve salicylic occupation rate according to the increment that reacts the front and back product.
It is as follows that the present invention prepares the structural characterization of product:
1, qualitative reaction
Respectively raw material and synthetics are carried out qualitative reaction by iron trichloride experiment and the experiment of hydroxamic acid iron, the results are shown in Table 1.
CTS-g-SA is for FeCl
3Test is purple; For the hydroxamic acid iron tests, take on a red color, illustrate that salicyloyl has been connected on the chitosan molecule skeleton.
2, solubleness test
Its solubleness rule of 2-CTS-g-SA of the different connection rates of this law synthetic is as follows: 75%>50%>20%>CTS; The solubleness of same grafts under acidic conditions is greater than the solubleness under the alkalescence, solubleness maximum during PH=3.
Table 1 SA-CTS qualitative reaction result
3, nucleus magnetic resonance
1H NMR spectrum
CTS's
1In the H NMR spectrum, the chemical shift of NH appears at 7.20259 and 6.99347ppm in the ethanamide residue; And CTS-SA's
1In the H NMR spectrum, the chemical shift of NH has taken place mobilely respectively in the amide residues to low place, appears at 7.7109 and 7.6769ppm, illustrates that the existence of salicyloyl has strengthened the effect of deshielding of NH; 6.8184 to the absorption peak of four fragrant hydrogen of difference between the 7.2168ppm, (Fig. 1,2 is respectively CTS and percentage of grafting 20%CTS-g-SA's to see Fig. 1 and Fig. 2
1H NMR spectrum).
Fig. 3 and Fig. 4 are respectively the IR spectrogram of the CTS-g-SA of CTS and percentage of grafting 20%.CTS is 3500 and 3309.6cm
-1The absorption peak at place is respectively the stretching vibration of amino and hydroxyl; 1595 and 1261cm
-1Be respectively the formation vibration of amino and hydroxyl; 1662cm
-1The place is the carbonylic stretching vibration of ethanamide.
CTS-g-SA is at 1251.7cm
-1The formation vibration of place's hydroxyl absorbs and strengthens 1595cm
-1The amino formation vibration in place obviously weakens.1550cm
-1Benzamide N-H bond bending vibration appears in the place, and 1458.1,1488.9cm
-1With 860.2,759.9cm
-1Phenyl ring C=C absorption appears respectively in the place and adjacent disubstituted benzenes=C-H absorbs, and illustrates that salicyloyl has been connected on the amino of CTS.
Embodiment
Embodiment 1, chitosan (deacetylation 92%) and Whitfield's ointment fed intake by 5: 3.5 weight to add in the reaction flask, the ethanol that adds 10 times, 60 ℃ of following stirring reaction 2.0hr, reclaim solvent, with the unreacted Whitfield's ointment of alcohol reflux wash-out, get 2-position CTS-g-SA grafts, average percentage of grafting 60%~70%.
Embodiment 2, chitosan (deacetylation 95%) and Whitfield's ointment fed intake by 6: 1.5 weight to add in the reactor, grinds 2hr.The ethanol that adds 30 times is done the entrainment agent component distillation.Suction filtration with the unreacted Whitfield's ointment of washing with alcohol, gets 2-position CTS-g-SA grafts, average percentage of grafting 20%~30%.
Embodiment 3, the 3g chitosan is inserted in the reactor; Get the 2.6g Whitfield's ointment with 9: 1 ethanol of 100ml volume ratio-benzene mixed solution dissolving, this solution is added in the reactor, stir backflow 0.5hr down, steam solvent.With the solids washing with alcohol, get 2-position CTS-g-SA grafts, average percentage of grafting 70%~75%.