SINTESIS SENYAWA ANALOG KURKUMIN DARI BAHAN DASAR VERATRALDEHIDA DAN BROMOVERATRALDEHIDA DAN UJI INHIBISINYA TERHADAP ENZIM ALFA GLUKOSIDASE

INTAN KURNIA PUTRI, Dra. Tutik Dwi Wahyuningsih, M.Si, Ph.D; Dr.Chairil Anwar

2016 | Tesis | S2 Ilmu Kimia

Telah dilakukan sintesis senyawa analog kurkumin (1-6) dari bahan dasar veratraldehida dan 6-bromoveratraldehida, dan uji anti diabetes senyawa hasil sintesis melalui uji inhibisi enzim α-glukosidase. Tahap sintesis melibatkan brominasi veratraldehida dan kondensasi aldol Claisen Schmidt veratraldehida atau bromoveratraldehida dengan variasi monoketon (sikloheksanon, siklopentanon atau aseton) menghasilkan senyawa analog kurkumin. Tahapan pertama yaitu sintesis senyawa bromoveratraldehida dengan mereaksikan veratraldehida dan HBr dengan katalis asam KBrO3 menghasilkan 6-bromoveratraldehida rendemen sebesar 80,00%. Tahapan kedua yaitu sintesis senyawa analog kurkumin (1-3) dengan merefluk campuran veratraldehida dan monoketon (sikloheksanon, siklopentanon, atau aseton) dengan katalis KOH menghasilkan rendemen berturut-turut sebesar 54,30; 69,20; dan 60,00%. Prosedur yang sama untuk sintesis analog kurkumin (4-6) dilakukan dengan mereaksikan 6-bromoveratraldehida dan monoketon (sikloheksanon, siklopentanon, atau aseton) menghasilkan rendemen masing-masing sebesar 36,84; 64,89; dan 34,63%. Elusidasi struktur terhadap semua produk yang diperoleh dilakukan dengan spektrometer FTIR, GC-MS, 1H- dan 13C-NMR. Uji inhibisi enzim α-glukosidase pada analog kurkumin (1-6) dilakukan menggunakan isolat enzim α-glukosidase dari beras lapuk. Hasil uji inhibisi enzim menunjukkan bahwa kurkumin 1 cukup berpotensi untuk menginhibisi enzim α-glukosidase dengan % inhibisi sebesar 88,53 pada konsentrasi 7,5 mM. Adanya gugus bromo pada senyawa analog kurkumin tidak menunjukkan pengaruh terhadap inhibisi enzim α-glukosidase.

Synthesis of curcumin analogues (1-6) from veratraldehyde and bromoveratraldehyde, and their inhibition toward α-glucosidase enzyme have been carried out. The stepwise synthesis was performed via veratraldehyde bromination and followed by Claisen-Schmidt aldol condensation to give curcumin analogues. First reaction of bromoveratraldehyde synthesis was started by reacting veratraldehyde with HBr in the presence of KBrO3 catalyst to give 6-bromoveratraldehyde in 80.00% yield. Next, the curcumin analogues (1-3) were synthesized by refluxing veratraldehyde and monoketone (cyclohexanone, cyclopentanone and acetone) with KOH as base catalyst. The products have been successfully synthesized in 54.34; 69.23; and 60.00% yield. In addition, the same procedure using bromoveratraldehyde and monoketone (cyclohexanone, cyclopentanone and acetone) yielded the curcumin analogues (4-6) in 36.84; 64.89; and 34.63%, respectively. The structure elucidation of all products were obtained from FTIR, GC-MS, 1H- and 13C-NMR spectrometers. Inhibition of α-glucosidase enzyme of curcumin analogues (1-6) was performed α-glucosidase enzyme isolated from molded rice. The result showed that curcumin 1 has potentially inhibit was α-glucosidase enzyme with %inhibition 88.53 at concentration 7.5 mM. There is no effect of bromo subtituent on inhibition α-glucosidase enzyme. .

Kata Kunci : Bromoveratraldehida, kurkumin analog, enzim α-glukosidase