Summary of chemistry dotoral thesis: Study on chemical constituents, cytotoxic and antiinflammatory activities of the sponges Rhabdastrella providentiae and Xestospongia muta living in the

Objectives of the thesis: Determine the chemical constituents of two marine sponge species Rhabdastrella providentiae and Xestospongia muta living in the sea area of Central Vietnam. Evaluate cytotoxic and anti-inflammatory activities of isolated compounds to seek for active compounds for further studies to develop healthy care products for the community.

MINISTRY OF EDUCATION AND TRAINING VIETNAM ACADEMY OF SCIENCE AND TECHNOLOGY GRADUATE UNIVERSITY OF SCIENCE AND TECHNOLOGY - STUDY ON CHEMICAL CONSTITUENTS, CYTOTOXIC AND ANTI-INFLAMMATORY ACTIVITIES OF THE SPONGES Rhabdastrella providentiae AND Xestospongia muta LIVING IN THE SEA AREA OF CENTRAL VIETNAM Major: Organic chemistry Code: 9.44.01.14 SUMMARY OF CHEMISTRY DOTORAL THESIS Ha Noi - 2019 This thesis was completed at: Graduate university of Science and Technology - Vietnam Academy of Science and Technology Advisor 1: Advisor 2: Reviewer 1: Reviewer 2: Reviewer 3: This thesis will be defended at Graduate University of Science and Technology - Vietnam Academy of Science and Technology at hour date month 2019 The thesis can be found in: - The Library of Graduate University of Science and Technology, Vietnam Academy of Science and Technology - National Library of Vietnam 2 INTRODUCTION The urgency of the thesis In recent years, with the fast development of advanced techniques, a large number of natural compounds have been actively isolated and evaluated for biological activities Many drugs from marine species have been available on the market by major pharmaceutical companies in the world such as: Cytarabine, Halaven, Ziconotide, Vidarabine, Trabectedin Vietnam has the advantage of a long coastline with more than 3,260 km from North to South and many coastal islands, notably Truong Sa and Hoang Sa archipelagoes located in the middle of East Sea Such geographical conditions have brought many advantages and potentials for rich natural resources, creating an extreme diversity and abundant marine ecosystem The research showed that there were about 160 marine sponge species distributed mainly in coastal and offshore islands Among them, there were only 20 species which have been studied on the chemical composition and biological activity Particularly, the sponge Rhabdastrella providentiae has not been studied in Vietnam and over the world The sponge Xestospongia muta has not been studied in Vietnam The study and survey of chemical constituents and biological activity of marine species are topic of interest for scientists in the world In Vietnam, there were some studies on chemical constituents and biological activity of marine species published in prestigious international magazines but not many Therefore, the task of studying the chemical composition and biological activities of marine life in our country is very important From that point, the topic "Study on chemical constituents, cytotoxic and antiinflammatory activities of the sponges Rhabdastrella providentiae and Xestospongia muta living in the sea area of Central Vietnam" was chosen Objectives of the thesis: + Determine the chemical constituents of two marine sponge species Rhabdastrella providentiae and Xestospongia muta living in the sea area of Central Vietnam 3 + Evaluate cytotoxic and anti-inflammatory activities of isolated compounds to seek for active compounds for further studies to develop healthy care products for the community The content of the thesis includes: Isolate compounds from two species of marine sponges Rhabdastrella providentiae and Xestospongia muta living in the sea area of Central Vietnam by chromatographic methods: Determine the chemical structure of compounds isolated by physical and chemical methods Evaluate in vitro cancer cell toxicity activity of isolated compounds; Evaluate in vitro anti-inflammatory activity of isolated compounds The objectives of the thesis Study on chemical constituents of two marine sponge species named Rhabdastrella providentiae and Xestospongia muta Evaluation of cytotoxic and anti-imflammatory biological activities of isolated compounds to seek for potential compounds for further researches The main contents of the thesis Isolation of compounds from the sponges Rhabdastrella providentiae and Xestospongia muta living in the sea area of Central Vietnam Determination of chemical structures of isolated compounds Evaluation of cytotoxic and anti-imflammatory biological activies of isolated compounds to provide scientific evidences for applied researches CHAPTER 1: OVERVIEW This chapter provides an overview on the sponges in all over the world and in Vietnam 1.1 Introduction to sponges This section introduces generally about the characteristics, distribution, studies of chemical constituents and biological activities of marine sponges 4 1.2 The study of sponges of the genus Rhabdastrella 1.3 The study of sponges of the genus Xestospongia CHAPTER 2: EXPERIMENT AND RESULTS 2.1 Sponge materials Sample of Rhabdastrella providentiae (Dendy, 1916) was collected at Con Co, Quang Tri, Vietnam Sample of Xestospongia muta (Schmidt, 1870) was collected at Vinh Moc, Quang Tri, Vietnam 2.2 Methods 2.2.1 Methods for isolation of secondary metabolites 2.2.2 Methods for determination of chemical structure of compounds 2.2.3 Cytotoxic assay 2.3 Isolation of compounds 2.3.1 Isolation of compounds from R providentiae Figure 2.1 Isolation of compounds from R providentiae 2.3.2 Isolation of compounds from X muta Figure 2.2 Isolation of compounds from X muta 2.4 Physical and spectroscopic data of compounds 2.5 Results on activity of compounds 2.5.1 Results on anti-inflammatory activity of compounds from R providentiae Table 2.1 The results of evaluation inhibited NO production activity in BV2 cells of compounds RP1-RP18 Compounds RP2 RP5 RP7 RP8 RP9 RP10 RP11 RP12 RP13 RP14 RP15 RP16 Butein IC50 (µM) 7.4 ± 0.4 75.3 ± 3.8 17.5 ± 0.9 46.8 ± 2.3 22.9 ±1.1 39.2 ± 2.0 26.3 ± 1.3 19.4 ± 1.0 29.4 ± 1.5 17.1 ± 0.9 19.5 ± 1.0 43.8 ± 2.2 4.5 ± 0.5 2.5.2 Results on anti-inflammatory activity of compounds from X muta Table 2.2 Inhibited NO production activity in BV2 cells of compounds XM1XM11 Compounds XM1 XM6 XM8 IC50 (µM) 4.9±0.24 11.5± 0.57 8.2 ± 0.41 4.4 ± 0.5 Butein 2.5.3 Results on cytotocic activity of compounds from R providentiae Table 2.3 Cytotocic activity of compounds RP1-RP18 Compounds RP1 RP2 RP3 RP7 Pos IC50 (µM) Hep-G2 LU-1 MCF-7 HL-60 SK-Mel 84.70±3.45 13.99±2.13 71.26±3.99 56.03±2.25 2.03 ± 0.3 84.82±6.67 14.75±1.30 63.38±2.45 62.20±3.41 1.96 ± 0.2 77.92±4.54 16.04±2.04 63.76±3.91 55.85±2.96 1.71 ± 0.2 56.14± 4.08 14.76± 1.31 46.33± 2.58 48.30± 3.73 2.16 ± 0.1 75.39± 4.83 11.16± 1.40 75.52± 6.69 37.96± 0.07 2.12 ± 0.3 Positive control: Ellipticine 2.5.4 Results on cytotocic activity of compounds from X muta Table 2.4 Cytotocic activity of compounds XM1-XM11 Compounds XM1 XM2 XM3 XM4 XM5 XM6 XM7 XM8 XM11 Pos Hep-G2 0.43±0.03 0.75±0.11 6.58±0.94 5.06±0.39 5.55±0.98 6.85±0.76 30.35±3.04 19.52±1.45 34.31±3.43 1.54 ± 0.37 LU-1 0.76±0.09 0.96±0.09 9.20±1.21 5.63±0.19 5.84±0.45 9.88±0.98 32.59±2.56 22.25±1.26 34.83±0.54 1.38 ± 0.16 Positive control: Ellipticine IC50 (µM) MCF-7 0.44±0.05 0.79±0.05 7.36±1.16 5.32±0.67 5.68±0.89 7.82±0.53 24.85±1.21 24.85±0.91 37.96±1.01 1.18 ± 0.12 HL-60 0.62±0.08 0.88±0.17 7.84±0.85 5.65±0.42 6.58±0.94 9.19±0.72 22.95±0.95 16.79±0.74 19.14±1.58 1.34 ± 0.24 SK-Mel 0.77±0.13 1.02±0.11 11.23±0.33 5.45±0.91 6.24±0.96 7.51±0.69 35.92±4.87 23.04±2.47 36.63±1.40 1.91 ± 0.28 Evaluation of anti-cancer mechanism of XM1 against MCF-7 - human breast cancer cell line: XM1 triggers cell apoptosis by altering the expression level of related proteins in human breast cancer cells MCF-7 At the same time, this compound also affects MCF-7 human breast cancer cell cycle in G2/M phase CHAPTER 3: DISCUSSIONS 3.1 Determination of chemical structure of compounds from R providentiae 3.1.12 Compound RP12: rhabdaprovidine G (new compound) Figure 3.30 Chemical structure of compound RP12 and RP10 Compound RP12 is a light yellow amorphous powder The molecular formula of compound RP12 was determined to be C30H46O4 by the exhibition of a quasi-molecular ion peak at m/z 493.3289 [M+Na]+ (calcd for C30H46O4Na: 493.3294) in the HR-ESI-MS The 1H-NMR spectrum of RP12 contained signals corresponding to seven methyl groups at δH 0.95, 1.05, 1.09, 1.49, 1.61, 1.68, 1.71, two olefinic protons at δH 5.10, 5.81, and three oxygenated methines at δH 4.15, 4.24, 4.70 ppm The 13CNMR of RP12 contained signals corresponding to 30 carbon atoms that were preliminary assigned, according to HSQC data, as one carbonyl carbon at δC 219.9; four olefinic carbons at δC 121.8, 124.1, 131.6, and 141.9; and three oxygenated methines at δC 68.1, 76.3, 77.0 The NMR spectral data of RP12 were compared with the corresponding data of compound RP10 (its structure was elucidated) and found to match from carbons C-1 to C-8, and different from carbon C-9, suggesting that the ring C (5C) of RP12 was changed This suggestion was further confirmed by HMBC and COSY correlations at rings A and B (Figure 3.32) 8 Table 3.12 NMR spectral data of RP12 and reference compound C 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 * δCa,b 31.2 33.4 218.8 46.9 45.2 18.9 35.8 41,2 50.6 34.5 34.4 207.1 123.6 172.2 19.3 23.5 - δCa,b 32.9 33.8 219.9 47.2 45.7 19.4 34.4 42,6 54.1 36,0 77.0 76.3 54.9 54.0 36.4 68.1 121.8 49.8 24.1 141.9 16.6 39.8 26.6 124.1 131.6 25.7 17.8 29.3 19.4 36.5 δHa,c (mult., J = Hz) 1.73 (m)/ 2.57 (m) 2.32 (m)/ 2.70 (m) 2.48 (dd, 2.5, 12.5) 1.41 (m)/ 1.58 (m) 1.40 (m)/ 2.04 (m) 1.90 (d, 3.0) 4.24 (br s) 4.15 (d, 5.5) 1.72 (d, 5.5) 1.13 (d, 13.5)/ 2.26 (dd, 6.0, 13.5) 4.70 (br dd, 6.5, 8.5) 5.81 (d, 8.5) 2.65 (d, 4.5)/ 2.76 (d, 4.5) 0.95 (s) 1.71 (s) 2.06 (m)/ 2.11 (m) 2.08 (m)/ 2.14 (m) 5.10 (t, 6.5) 1.68 (s) 1.61 (s) 1.09 (s) 1.05 (s) 1.49 (s) CDCl3, b125MHz, c500MHz *δC of RP10 The COSY cross peaks H-9 (δH 1.90)/ H-11 (δH 4.24)/ H-12 (δH 4.15)/ H-13 (δH 1.71) and HMBC correlation between H-30 (δH1.49) and C13 (δC 54.9) established five-membered ring C in RP12 The chemical shifts of C-11 (δC 77.0), C-12 (δC 76.3), and C-13 (δC 54.9) characterized for a two oxygenated methines (C-11 and C-12) and one aliphatic methine (C13) Other connections of carbon backbone were established by consecutive analysis of HMBC and COSY spectra, including HMBC correlations between terminal methyl protons H-26 (δH 1.68)/ H-27 (δH 1.61) and C-25 (δC 131.6)/ C-24 (δC 124.1), COSY cross peaks H-24 (δH 5.10)/ H-23 (δH 2.08, 2.14)/ H-22 (δH 2.06, 2.11), HMBC correlations between H-21 (δH1.71) and C-22 (δC 39.8)/ C-20 (δC 141.9)/ C-17 (δC 121.8), COSY cross peaks H-17 (δH 5.81)/ H-16 (δH 4.70)/ H-15 (δH 1.13, 2.26), HMBC correlations between H-18 (δH 2.65, 2.76) and C-15 (δC 36.4)/ C-14 (δC 54.0)/ C-13 (δC 54.9) In addition, an HMBC correlation between H-16 (δH 4.70) and C-12 (δC 76.3) indicated an ether bridge between C-16 and C-12 Also, the presence of an epoxide ring at C-14/C-18 was conclusively confirmed by the molecular formula of RP12 (C30H46O4), chemical shift of the methylene carbon C-18 (δC 49.8), the presence of a non-protonated carbon C-14 (δC 54.0), the J-coupling constant of geminal protons H-18 (4.5 Hz), and by comparison with previously published data The stereochemistry of compound RP12 was then proposed by analysis of NOESY and CD spectra An E-configuration of double bond C-17/C-20 was confirmed by a NOESY correlation between H-16 (δH 4.70) and H-21 (δH 1.71) NOESY correlations between H-19 (δH 0.95) and H-9 (δH 1.90)/ H-29 (δH 1.05), H-5 (δH 2.48) and H-28 (δH 1.09)/ H-30 (δH 1.49) indicated a trans-syn-trans junction between rings A-C (Figure 3.32) This means that C-29, C-19, and H-9 are located on the same side, assuming a βconfiguration Therefore, the NOESY correlations H-19 (δH 0.95)/ H-11 (δH 4.24), H-9 (δH 1.90)/ H-15ax (δH 2.26), H-15ax/ H-16 (δH 4.70) indicated β-configurations for H-11 and H-16 Additional NOESY correlations H-17 (δH 5.81)/ H-12 (δH 4.15), and H-12/H-13 (δH 1.71) suggested an α-configuration of H-12 and H-13 The epoxide ring at C14/C-18 adopted an α-configuration based on the NOESY correlation between H-30 (δH 1.49) and H-18 (δH 2.76) Finally, an absolute structure of RP12 was deduced by the similarity of experimental CD spectrum of RP12 in comparison with that of calculated CD spectrum for enantiomer RP12a (5R,8S,9S,10S,11S,12S,13S,14S,16S, Figure 3.33) Consequently, structure of compound RP12 was established and named as rhabdaprovidine G 10 Figure 3.31 Chemical structure and important HMBC, COSY and NOESY correlations of compound RP12 3.1.19 Total compounds isolated from R providentiae RP1-RP18 18 compounds (RP1-RP18) were isolated from the marine sponge Rhabdastrella providentiae These include: 12 new compounds (RP1RP12) named: rhabdastrellins G-K (RP1-RP5), rhabdaprovidines A-G (RP6-RP12) and known compounds: jaspolide C (RP13), globostelletin C (RP14), globostelletin D (RP15), jaspiferin A (RP16), mollisolactone A (RP17), gibepyrone F (RP18) (Figure 3.50) Besides, some of these isolated compounds demonstrate some specically structural characteristics such as: - The new compound RP12 has a complex structure with chiral carbons and an epoxy ring closure forming a 5-rings system was first found in isomalabaricane frame compounds In this study, we have determined the absolute configuration of RP12 through NOESY and CD spectrum analyses - The new compound RP11 with a special three-ring stereotype is arranged trans-syn-cis instead of trans-syn-trans often found in marine sponge Rhabdastrella species The absolute configuration of -RP11 is also determined through NOESY and CD spectra - The new compound RP3 has a γ-lactone ring closure in the vascular fraction is rarely found in isomalabaricane compounds The absolute configuaration of two chiral carbons at the side chain of this compound are also determined through analysis of δC values, NOESY and CD spectral interactions - In previous publications on the isomalabaricane skeleton, the 13E/13Z isomers are often reported as a mixed form (as globostelletin C and globostelletin D) In this study, new compounds RP4/ RP5, RP6/ RP7 and 11 two known compounds RP14/RP15 are 13E/13Z isomer pairs, however, they were separated one by one with high purity Figure 3.50 Chemical structure of compounds RP1-RP18 - The isomalabaricane skeleton compounds are specialized secondary substances synthesized by marine species like Stelletta, Jaspis, Geodia and Rhabdastrella (of the family Astrophorida) Therefore, the detection of new isomalabaricane compounds (RP1-RP12) can be considered as marker compounds to identify marine species of Rhabdastrella The special structure of compounds RP11 and RP12 can be used as an indicator for identification of R providentiae species 12 3.2 Determination of chemical structure of compounds from X muta 3.2.1 Compound XM1: araguspongine C Figure 3.51 Chemical structure of compound XM1 The compound XM1 was obtained in the form of a white, amorphous powder TLC analysis showed that XM1 reacted positively with Dragendorff's solution suggesting for an alkaloid compound Compound XM1 was shown to have a chemical formula similar to that of araguspongine C, C28H50O4N2, which was deduced from a cluster of quasi molecular ion peaks in the HR-ESI-MS at m/z 479.3845 [M+H]+ (Calcd for [C28H51O4N2]+, 479.3843), 501.3656 [M+Na]+ (Calcd for [C28H50O4N2Na]+, 501.3663), and 477.3701 [M−H]ˉ (Calcd for [C28H49O4N2]−, 477.3692) The chemical structure of araguspongine C was presented to form by symmetric cycloaddition of a pair of 9-hydroxy-1-oxaquinolizidine moieties through C6 linear chains The 1H NMR and 13C- NMR spectral data of XM1 indicated that two these compounds share the same macrocyclic bis-1oxaquinolizidine skeleton Interestingly, only 14 carbon signals were observed in the 13C NMR spectrum of XM1, which also suggested the symmetricity of its chemical structure Hence, detailed chemical structure of XM1 was elucidated on a half of its molecule HMBC correlations from H-10 (δH 4.10) to C-4 (δC 53.2) and C-6 (δC 45.5), and their chemical shifts, demonstrated connections of C-10, C-4, and C-6 via nitrogen atom to form a quinolizidine backbone Moreover, replacement by an oxygen atom at C-1 of the quinolizidine structure of XM1 was confirmed by the presence of oxygenated carbon signals of C-10 (δC 91.0) and C-2 (δC 77.6) and by HMBC correlation between H-10 and C-2 In addition, a singlet signal of 13 H-10 and HMBC correlations from H-10 to the non-protonated C-9 (δC 72.0), and methylene carbons C-8 (δC 33.8)/C-11 (δC 41.3) indicated the presence of a hydroxy group and linear carbon chain at C-9 It was hypothesized that C6-linear chain arises from the C-9 Thus, HMBC correlation from H-2 to C-16′ and COSY cross peak of H-2/H-16′ indicated head-to-tail cyclization of two half molecules of XM1 by connections C2/C-16′: C-16/C-2′ Due to the presence of a system with two fused sixmembered rings and three chiral carbons, stereochemistry of XM1 was studied by NOESY and conformational analyses It was assumed that both six-membered rings were in a stable chair forms Thus, as in decalin, cis- or trans-fused conformations should be acquired for a 1-oxaquinolizidine structure (Figure 3.53) Table 3.19 NMR spectral data of XM1 and reference compound δCd δCb,d δCa,b δHa,c (mult., J = Hz) 2, 2′ 76.8 76.4 77.6 3.60 (br dd, 10.5, 10.5) 3, 3′ 26.4 25.9 26.9 4, 4′ 52.9 52.4 53.2 6, 6′ 44.6 44.2 45.5 7, 7′ 21.3 20.8 21.8 1,79 (dddd, 4.0, 10.5, 13.0, 13.0) 1,13 (br d, 13.0) 3.15 (ddd, 2.5, 13.5, 13.5) 2,99 (br dd, 3.5, 13.5) 3.09 (br dd, 11.5, 11.5) 2.40 (br d, 11,5) 1.94 (m)/ 1.49 (m) 8, 8′ 30.0 29.6 33.8 9, 9′ 71.1 70.7 72.0 1.54 (ddd, 4.0, 11.0, 11.0) 1,39 (br d, 11,0) - 10, 10′ 90.7 90.3 91.0 4.10 (s) 11, 11′ 39.0 38.5 41.3 1.70 (ddd, 4.0, 13.0, 13.0)/1.23 (m) 12, 12′ 23.0 22.5 23.7 1.47 (m)/ 1.35 (m) C # 13, 13′ 32.7 32.2 33.0 1.30 (m)/ 1.28 (m) 14, 14′ 31.9 31.5 31.0 1.45 (m)/ 1.28 (m) 15, 15′ 25.3 24.9 26.3 1.60 (m)/ 1.33 (m) 16, 16′ 36.7 36.3 37.6 1.58 (m)/1.38 (m) a CD3OD, b125MHz, c500MHz, dCDCl3, #δC of araguspongine C 14 In the 1H-NMR spectrum, the splitting pattern of signals of H-2 (δH 3.60), H-3a (δH 1.79), H-4a (δH 3.15), H-6a (δH 3.09), and H-8a (δH 1.54) showing a large J axial-axial coupling constant (10.5 ~ 13.5 Hz) indicated that they are axial orientations The NOE correlations between H-2 (δH 3.60) and H-10 (δH 4.10), H-10 and H-4a (δH 3.15) were observered confirming the axial orientation of H-10 in ring B of compound XM1 The NOE correlation between H-8a (δH 1.54) and H-11 (δH 1.70) suggested the equatorial orientation of C-11 and hydroxy group at C-9 should be in an axial orientation Finally, the occurrence of a fusion in the (b)-cis form between the two six-membered rings was deduced by NOE correlation between H-3a (δH 1.79) and H-6a (δH 3.09) as shown in Figure 3.54 Therefore, the chemical structure of XM1 has been determined This compound has been isolated from a number of species such as X exigua, Haloclona exigua and is often called araguspongine C 13C-NMR data of XM1 was reanalyzed in CDCl3 and found to completely similar with the reported 13C-NMR data of araguspongine C in the same NMR measurement solvent Figure 3.52 Sustainable configuration of 1-oxa-quinolizidine flame Figure 3.53 The main NOE interactions in the 1-oxa-quinolizidine skeleton of compound XM1 15 3.2.12 Total of compounds isolated from X muta XM1-XM11 From the marine sponge of Xestospongia muta, 11 compounds (XM1-XM11) were isolated and determined the chemical structures (Figure 3.78): all of 11 compounds are macrocyclic bis-quinolizidine alkaloids skeleton, including new compound (XM2) named meso - araguspongine C and 10 known compounds: araguspongine C (XM1), araguspongines N-P (XM3-XM5), araguspongine A (XM6), araguspongine E (XM7), araguspongine L (XM8), petrosin (XM9), petrosin A (XM10), aragupetrosine A (XM11) The structures of these compounds contains 1oxa-quinolizidine unit, two quinolizidine units, or a combination of 1-oxaquinolizidine and quinolizidine units Some compounds consist of symmetrically chemical structure such as XM1, XM2, XM3, XM9, XM10 The highlights in structural analyses of compounds isolated from X muta species are mentioned below: Figure 3.78 Chemical structure of XM1-XM11 compounds 16 - The stereochemistry of new compound XM2 was determined based on a detailed analysis of the J coupling constant, structural analyses and spatial interaction on NOESY - Although XM3-XM4 are known compounds, however they have been structurally and chemically analyzed herein for the first time - Because up to now, only more than 20 compounds of macrocyclic bis-1oxa-quinolizidine skeleton have been reported in Xestospongia species, so that, compounds XM1-XM11 can also be used as marker compounds to indentify Xestospongia species 3.3 Evaluation of the biological activities of isolated compounds 3.3.1 Anti-inflammatory activity of compounds isolated from R providentiae After a preliminary assessment of the effect of inhibiting NO production in BV2 cell was stimulated by LPS of 18 compounds (RP1RP18) at concentration of 80 µM, the compounds RP2, RP5, RP7-RP16 are not cytotoxic and capable of inhibiting> 50% of NO production in BV2 cell Therefore, these substances are further tested at different concentrations to determine the IC50 value The results (Table 2.1) showed that: RP2 compounds exhibited the strongest inhibitory effect on NO production in BV2 cell with IC50 values of 7.4 ± 0.4 µM Compounds RP7, RP9, RP11-RP15 exhibit remarkable inhibitory effects on NO production with IC50 values of 17.1-29.4 µM The compounds RP8, RP10, RP16 show inhibitory effects on NO production with IC50 values of 39.2-46.8 µM The remaining compound RP5 shows the weakest inhibitory effect on NO production in BV2 cell with the value of IC50 75.3 ± 3.8 µM According to the literature review, there have been no studies of anti-inflammatory activity of isomalabaricane analog skeleton compounds This study can be used as a premise for further studies on the antiinflammatory activity of compounds RP2, RP7, RP9, RP11-RP15 17 3.3.2 Anti-inflammatory activity of compounds isolated from X muta The results of assessing the effect of 11 compounds (XM1-XM11) on BV2 cell growth at the test concentrations (20, 40 and 80 µM) showed that the XM2-XM5 and XM7 compounds are dead cells (> 30%) at concentrations of 40 and 80 µM However, these compounds not affect the normal development of BV2 cells at concentrations