350
Volume 5, Issue 10: Special Issue
(EJAR)
ISSN: 2181-2020
MPHAPP
THE 6TH INTERNATIONAL SCIENTIFIC AND PRACTICAL
CONFERENCE “MODERN PHARMACEUTICS: ACTUAL
PROBLEMS AND PROSPECTS”
TASHKENT, OCTOBER 17, 2025
in-academy.uz
SYNTHESIS OF GALACTOMANNAN DIALDEHYDE DERIVATIVES AND
INVESTIGATION OF THEIR PHYSICAL AND CHEMICAL PROPERTIES
Amono a D.M1.
Boydedae A.A1.
Ka imo M. Sh1.
Kalono a M.O1.
Muhi dino B.I1.
Tu ae A.S1.
Huang Y2.
Wang H2
1Ins i u e o Bioo ganic Chemis y, Uzbekis an Academy o Sciences, Tashken ci y, Republic
o Uzbekis an
2Shanghai Ins i u e o Ma e ia Medica, Chinese Academy o Sciences, Shanghai ci y, China
e-mail: [email p o ec ed]
h ps://doi.o g/10.5281/zenodo.17337447
Galac omannan is a polysaccha ide mainly composed o D-mannose and D-galac ose, linked
by α-1,4 and -1,6 glycosidic bonds. These connec ions de ine he s uc u e o he polysaccha ide
and in luence i s physicochemical p ope ies. The s uc u e can a y, wi h di e en b anching om
galac ose esidues a ec ing i s o e all cha ac e is ics. Dialdehyde de i a i es o galac omannan a e
no el compounds o med h ough oxida ion o chemical modi ica ion. These de i a i es enhance he
polyme 's igidi y, solubili y, and mechanical s eng h. They can also eac wi h p ima y amino
g oups, o ming imino (azome hine) bonds and Schi bases, which a e signi ican in a ious
applica ions. This s udy explo es he p oduc ion o low molecula weigh galac omannan dialdehyde
de i a i es, hei eac ion condi ions, and hei physicochemical p ope ies.
In his s udy, we de eloped and cha ac e ized dialdehyde de i a i es h ough he pe ioda e
oxida ion o low molecula weigh galac omannan, ob ained by depolyme izing gua galac omannan
a a concen a ion o 20 mg/ml in dis illed wa e . A eshly p epa ed 0.2 N sodium pe ioda e (NaIO4)
solu ion was added, main aining a galac omannan o sodium pe ioda e mola a io o 1:0.1-1.0. The
eac ions ook place in he da k a 40°C o 1 o 24 hou s. To s op he eac ion, 0.5 ml o e hylene
glycol was added. The esul ing p oduc was p ecipi a ed wi h 96% ( / ) e hanol (1:5 a io), washed
ou imes wi h 70% ( / ) e hanol o emo e impu i ies, dialyzed in he da k, il e ed, and lyophilized
o ob ain he inal p oduc . The s uc u es o he galac omannan dialdehyde de i a i es we e analyzed
using IR and 13C NMR spec oscopy.
In he IR spec oscopy s udies, he dialdehyde de i a i es o galac omannan exhibi ed
abso bance cha ac e is ic o N-H and O-H s e ching ib a ions in he ange o 3200-3600 cm⁻¹.
Signals ela ed o H–C–H (-CH₂-) and C=O (aldehyde) s e ching ib a ions we e obse ed a 2820-
2950 cm⁻¹ and 1732 cm⁻¹, espec i ely. Abso bances in he 1300-1400 cm⁻¹ egion co espond o he
de o ma ional ib a ions o C–H bonds, while hose a 1060 cm⁻¹ a e a ibu ed o he alence
ib a ions o C–O–C bonds in he glucopy anose ing. Abso bances a 894 cm⁻¹ a e cha ac e is ic o
he β-(ManC1−O−ManC4) glycosidic bonds be ween mannose esidues in he polyme chain.
Addi ionally, abso bances co esponding o he Man(C6)−O−Gal(C1) glycosidic bonds be ween
mannose and galac ose esidues we e iden i ied a 870 cm⁻¹. In he 13C NMR spec um, signals wi h
high in ensi y co esponding o he hemiace al and gem-diol o ms o polysaccha ides we e iden i ied
in he anges o 87-98 ppm. Speci ically, in he ange o 80.10-80.17 ppm, high-in ensi y signals
co espond o he ca bon a oms ManC2 and ManC3 in he hemiace al and gem-diol o ms,
351
Volume 5, Issue 10: Special Issue
(EJAR)
ISSN: 2181-2020
MPHAPP
THE 6TH INTERNATIONAL SCIENTIFIC AND PRACTICAL
CONFERENCE “MODERN PHARMACEUTICS: ACTUAL
PROBLEMS AND PROSPECTS”
TASHKENT, OCTOBER 17, 2025
in-academy.uz
espec i ely. This indica es ha he pe ioda e oxida ion in galac omannans p ima ily occu s a he
ca bon a oms ManC2 and ManC3.
This s udy de eloped low molecula weigh galac omannan dialdehyde de i a i es and
ho oughly in es iga ed hei p ope ies. The ob ained galac omannan dialdehydes we e analyzed
using IR and 13C NMR spec oscopy echniques. The IR spec oscopy esul s indica ed ha he C=O
(aldehyde) s e ching was obse ed a 1732 cm⁻¹. The 13C NMR spec um con i med he unique
cha ac e is ics o he galac omannan s uc u e, showing ha he pe ioda e oxida ion occu ed a he
ManC2 and ManC3 ca bon a oms. The esul ing dialdehyde de i a i es play a c ucial ole in
enhancing he polyme 's igidi y, solubili y, and mechanical s eng h, c ea ing new oppo uni ies o
hei use in a ious indus ial and biological applica ions.
