Dysoticans F–H: three unprecedented dimeric cadinanes from Dysoxylum parasiticum (Osbeck) Kosterm. stem bark

Abstract

Dysoxylum parasiticum's stem bark produces an asymmetrical and two symmetrical dimers (1–3), dysoticans F–H, with a novel cadinene dimer skeleton.

Immunomodulatory of sesquiterpenoids and sesquiterpenoid dimers-based toll-like receptor 4 (TLR4) from Dysoxylum parasiticum stem bark

“…The phytochemical investigation of the n- hexane extract of D. parasiticum yielded sesquiterpenoids (SQs): 10 β ,11-dihydroxy-1 β -hydroperoxide-4 α H ,5 α H ,7 β H -guaiane ( 1 ), (1 S *,4 S *,5 R *,10 S *)-guai-6-ene-10 β -ol ( 2 ), guaianediol ( 3 ), 4 α ,10 α ,11-trihydroxy-1 β H ,5 β H -guai-7(8)-ene ( 4 ), spathulenol ( 5 ), 4 β -10 α -dihydroxyaromadendrane ( 6 ), 10 β -hydroxy-4 α ,4 β - dimethyl-5 α H ,7 α H -eudesm-3-one ( 7 ), α -cadinol ( 8 ), 10-hydroxyl-15-oxo- α -cadinol ( 9 ), dysoticans A and B ( 10 ) and ( 11 ), 2,15-dihydroxycalamenene ( 12 ), schiffnerone B ( 13 ), aristegelone A ( 14 ), eudesm-4(15)-ene-1 β ,6 α -diol ( 15 ), and eudesm-4(15)-ene-1 β ,6 β -diol ( 16 ) and sesquiterpenoid dimers (SQDs): dysoticans C-H ( 17–22 ), including four SQs 1 , 7 , 10 , and 11 and six SQDs 17–22 that were first discovered from this plant (Fig. 1 ) after separation using normal and reverse techniques of column chromatography 22 – 24 . The potential immunomodulatory effect of 22 pure compounds was assessed in an experimental model of macrophage activation through the TLR4 signaling pathway.…”

“…The dried stem bark was powdered and extracted with MeOH. Subsequently, 16 SQs and 6 SQDs were isolated from the n- hexane and ethyl acetate extracts by chromatography over silica gel, followed by purification on reverse phase ODS, as described in previous publications 22 – 24 .…”

“…The species is popularly known as “Majegau” or divine tree due to its characteristic fragrances. The pioneer phytochemical investigations of this plant carried out by our group afforded 16 sesquiterpenoids (SQs) and six sesquiterpenoid dimers (SQDs), involving four SQs and six SQDs, first found from this plant 22 – 24 . Since the potential of all SQs and SQDs as immunomodulatory remains unexplored, this study aimed to investigate the immunomodulatory activity based on TLR4 receptors.…”

Sesquiterpenoids from Meliaceae Family and Their Biological Activities

“…Moreover, the cytotoxic activity of ( 210 ) is a selective inhibitor against the HeLa cell growth with an IC 50 value of 39.72 ± 0.18 µM. All compounds are compared to cisplatin with IC 50 values 53.00 ± 0.02 and 16.00 ± 0.01 µM [ 120 ].…”

“…Additionally, two unprecedented homo-dimeric sesquiterpenoids, dysotican G (209) and dysotican H (210), which linked through O-ether linkage and an asymmetrical true-dimeric cadinane via ketonic bridge dysotican F (211), were isolated from the stembark of Dysoxylum parasiticum. Their structure was determined by spectroscopic and quantum chemical calculations of 13 C NMR using the GIAO method and ECD using the TDDFT method [120].…”