Metabolites profiling of ethyl acetate extract of sponge Halichondriidae sp from Kangean Islands and their in silico activity as coronavirus drugs

The Corona Virus Disease-2019 (COVID-19) pandemic gives a challenge for scientist to develop the most promising drug candidate from every potential natural product, including marine biodiversity. Marine natural products have rarely explored since the difficulties in the sample collection. In this study, we reported the isolation of marine sponge Halichondriidae sp. from the Kangean Islands using ethyl acetate as a solvent. The profiling of the ethyl acetate fractions leading to the presence of aliphatic and aromatic hydrocarbon with specific functional groups, such as, amines, alcohols, amides, carbonyls, and halides. further analysis using LC-ESI-MS/MS showed the presence of 4-(1,3-Dibenzyl-2-imidazolidinyl)-N,N-dimethylaniline as the main compound. The other is 4-{7-[2-hydroxy-2-(4-nitrophenyl)ethyl]-3-methyl-2,6-dioxo-1,2,3,6,7,9-hexahydro-8H-purine-8-ylidene}morpholin-4-ium, erucamide, nepafenac, 1-benzofuran-2-carbonitrile, 1,3-dibenzyl-2-(6-methyl-2-pyridinyl)hexahydropyrimidine, N,N,N-Tributyl-1-butanaminium-2-hydroxypropanoate, (±)-anabasine, benzyl urea, tert-butyl isopropylcarbamate, 3-(4-Hexylcyclohexyl)-5-undecyl-1,2,4-oxadiazole and 2-[(2E)-2-octadecen-1-yl]succinic acid. Molecular docking analysis using 7L0N as one of COVID-19 receptor with 4-{7-[2-Hydroxy-2-(4-nitrophenyl) ethyl]-3-methyl-2,6-dioxo-1,2,3,6,7,9-hexahydro-8H-purin-8-ylidene} morpholin-4-ium suggested the lowest binding energy is -6.277±0.04726 kcal/mol. The dominan interaction of the receptor and ligand are hydrogen bonding, hydrophobic bond from ℼ-alkyl interaction, hydrogen-carbon interactions and Van der Waals interactions.