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Synthesis of 1-azabicyclo[3.2.2]nonane from cinchonidine Mujahidin, Didin; Hoffman, Hans Martin Rudolf
Jurnal Penelitian Teh dan Kina Vol 16, No 2 (2013)
Publisher : Research Institute for Tea and Cinchona

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (319.14 KB) | DOI: 10.22302/pptk.jur.jptk.v16i2.89

Abstract

The 1-azabicyclo[3.2.2]nonane is a potent building block which have important bio­logicaly activities including for Alzheimer and ashmatic treatment. The skeleton can be accessed by rearrangement of quinuclidine ring in Cinchona alkaloids. The rearrange­ment established three chiral center at C-2, C-3, and C-6. The rearrangement of qui­nuclidine moiety to azabicyclic[3.2.2]nonana system of mesylated cinchonidine took place by hydrolysis in a mixture of acetone–water (1:1) with 47% yields. The structure determination of the product and its absolute configuration of chiral centers were esta­blished by using spectroscopy data including, 1H NMR, 13C NMR, 1D NOE and HR-MS.
The oxidation reaction of quinine by potassium permanganate (KMnO4) Rosalina, Reny; Alni, Anita; Mujahidin, Didin; Santoso, Joko
Jurnal Penelitian Teh dan Kina Vol 18, No 2 (2015)
Publisher : Research Institute for Tea and Cinchona

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (588.892 KB) | DOI: 10.22302/pptk.jur.jptk.v18i2.76

Abstract

Quinine was known widely as malarial drug and a bitter taste ini soft drink. Recently, quinine have been also applied in organo-catalysis process, separation and purification of chiral compounds from enantiomeric mixture by diasteromeric salt crystallization and chiral chromatography. Quinine contains various functional groups which easily transforms by oxidations. This research was to study the oxi-dation reaction of quinine by using potassium permanganate (KMnO4) as oxidator. The KMnO4 oxidation carried out under acidic con-ditions. The separation and purification of pro-ducts were done by radial chromatography with chloroform : metanol : tri ethyl amine (9:1:0.1) as eluent. The structure of products were cha-racterized by spectroscopic data including: in-frared spectroscopy, NMR, and mass spectro-metry as quinine-1-N-oxide and quininal.
Synthesis of quinine N-oxide and an NMR tutorial in its structure determination Aisyah, Aisyah; Tamaela, Nila Berghuis; Santoso, Joko; Syah, Yana Maolana; Mujahidin, Didin
Jurnal Penelitian Teh dan Kina Vol 17, No 1 (2014)
Publisher : Research Institute for Tea and Cinchona

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (637.555 KB) | DOI: 10.22302/pptk.jur.jptk.v17i1.45

Abstract

Cinchona alkaloids are one of abundant natural chiral pool for organocatalysts. The application of an N-oxide group containing molecule in asymmetric reaction is currently wide developed. The structure of quinine consist two amine groups that could be oxidized to the N-oxide groups at N-1’ of quinoline and at N-1 of quinuclidine moieties. The oxidation reaction took place selectively at quinuclidine moiety by controlling the concentration of oxidizing agents. In this study we showed that N-1-oxide quinine could be occurred chemo­selectively by using a low concentration of ozone thana palladium catalyzed oxidation. The structure of products N1-oxide quinine was elucidated by spectroscopy data including 1H-NMR, 13C-NMR, 2D-NMR, infra-red and mass spectrometry. The developed method is a chemoselectively and eco-friendly method for synthesis N1-oxide quinine.
Discovery of thymol-fused chalcones as new competitive \(\alpha\)-glucosidase inhibitors: Design, synthesis, biological evaluation, and molecular modeling studies Danova, Ade; Hermawati, Elvira; Chavasiri, Warinthorn; Mujahidin, Didin; Alni, Anita; Roswanda, Robby
Communications in Science and Technology Vol 9 No 2 (2024)
Publisher : Komunitas Ilmuwan dan Profesional Muslim Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21924/cst.9.2.2024.1497

Abstract

This study aims to synthesize and evaluate the inhibitory activity of thymol derivatives targeting ?-glucosidase using in vitro and in silico studies. Ten thymol derivatives (2-11) including five new thymol-fused chalcones (7-11) were successfully synthesized. Among them, four compounds (4, 8, 9, 11) showed the best inhibitory activity with IC50 values of 18.45, 13.75, 8.86, and 10.67µM compared with acarbose (IC50 = 832.82 µM), respectively. The kinetic study of three new thymol-fused chalcones (8, 9, 11) exhibited a competitive inhibition. Molecular docking demonstrated the predicted interactions between ligand (8, 9, 11) and ?-glucosidase, which are responsible for inhibiting the enzyme's catalytic abilities. Furthermore, molecular dynamics simulation of the enzyme-ligand 9 complex indicated that this complex was stable in aqueous condition. This research contributes significantly to the understanding of thymol-fused chalcones that may have therapeutic potential and their possible application in the treatment of type 2 diabetes mellitus (T2DM) for further study.
In vitro evaluation, molecular docking, and molecular dynamics studies of resorcinol derivatives against yeast α‐glucosidase Danova, Ade; Hermawati, Elvira; Chavasiri, Warinthorn; Mujahidin, Didin; Musthapa, Iqbal; Kurniadewi, Fera
Indonesian Journal of Biotechnology Vol 30, No 3 (2025)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijbiotech.106495

Abstract

Nine resorcinol derivatives were evaluated for their ability to inhibit yeast α‐glucosidase using the in vitro method. Three molecular docking programs (Autodock Vina, Autodock4 and DockThor) were employed to determine the binding energies. The results showed that two resorcinol derivatives possessing butanoyl (1) and butyl (9) groups demonstrated good inhibitory activity against α‐glucosidase, with IC50 values of 75.9 and 33.3 µM respectively, compared with other derivatives (2–8) and acarbose (IC50 = 832.8 µM). Furthermore, molecular docking indicated that compounds 1 and 9 had better binding affinities than acarbose and the native ligand. Both compounds showed similar interactions with Asp349 and Glu408, which were associated with acarbose and the native ligand. Moreover, molecular dynamics analysis indicated that compound 9 exhibited greater stability than compound 1 when complexed with α‐glucosidase. Therefore, compound 9 has the potential for further studies, both in vitro and in vivo, to evaluate its toxicity, side effects and efficacy.
Anti-tyrosinase Activity of 3’,4’,5’-Trimethoxychalcones: Experimental and Computational Studies Danova, Ade; Hermawati, Elvira; Chavasiri, Warinthorn; Mujahidin, Didin; Musthapa, Iqbal; Kurniadewi, Fera
Science and Technology Indonesia Vol. 10 No. 4 (2025): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2025.10.4.982-989

Abstract

Tyrosinase inhibitors are utilized as preservatives in the food industry and skin-lightening agents in the medical and cosmetic sectors. However, there has been little progress in clinical trials owing to challenges such as low bioavailability, significant skin irritation, and instability. Hence, the objective of this study was to evaluate the inhibitory activity of 3’,4’,5’-trimethoxychalcones through in vitro, molecular docking and molecular dynamics studies targeting tyrosinase. Five 3’,4’,5’-trimethoxychalcones (1-5) were evaluated their biological activity against tyrosinase for the first time. Compounds 4 and 5 were excellent inhibitory activity against tyrosinase with IC50 values of 1.9 and 1.7 μm compared with kojic acid and ascorbic acid. Isovanillin and catechol moieties are vital in this present study. This result was supported with molecular docking by shaping interaction in the catalytic site with histidine residues and the stability evaluation of the inhibitor-protein complexes using molecular dynamics simulation. The lipinski’s rules showed a fit with two potential inhibitors (4, 5). Therefore, 3’,4’,5’-trimethoxychalcones possessing isovanillin and catechol parts in the B ring are promising candidate for further study as tyrosinase inhibitors by evaluating their efficacy in vitro and in vivo.