6619-95-0

Upstream product

• 6619-96-1 Methyl 15β-hydroxy-ent-kaur-16-en-19-oate 
• 6619-97-2 15β–acetoxy–(–)–kaur–16–en–l9–oic acid 
• 5095-09-0 kaurenoic acid 
• 6619-97-2 15α-Acetoxy-Δ¹⁶-kauren-18α-saeure 
• 6619-97-2 ent-15α-acetoxy-kaur-16-en-19-oic acid 

Downstream Products

• 22376-47-2 methyl ent-15-oxokaur-16-en-19-oate 

Relevant academic research and scientific papers

Microbial transformation of ent-kaurenoic acid and its 15-hydroxy derivatives by the SG138 mutant of Gibberella fujikuroi

Feeding experiments with ent-kaurenoic acid (4), 15αc-hydroxy-ent-kaurenoic acid (5), 15β-hydroxy-ent-kaurenoic acid (6), and mixtures of 4 plus 5 and 4 plus 6 were conducted using the SG138 mutant of Gibberella fujikuroi, to gain information about the phenotype of this unique strain. The biotransformation of 5 gave 7β15α-dihydroxykaurenolide (9) and 7β,15α-dihydroxy-ent-kaurenoic acid (13). The incubation of 6 produced 7β, 15β-dihydroxy-ent-kaurenoic acid (7) and 7β,15β-dihydroxykaurenolide (10). No 15-hydroxylated gibberellins were detected in any of these experiments. The results indicated that a hydroxy group at C-15 does not inhibit 7β-hydroxylase activity but in the SG138 strain obstructs the enzymatic ring-B contraction of ent-kaurenoids to gibberellins. Exogenous 4 stimulated both the excretion of ent-kaurene and the fungal metabolism of 5 and 6.

Synthesis of a new allelopathic agent from the biotransformation of ent-15α-hydroxy-16-kauren-19-oic acid with Fusarium proliferatum

The use of kaurane diterpenes as substrates in fungal biotransformation to achieve bioactive compounds has been widely reported. In this work, the natural product kaurenoic acid, a diterpene widely distributed in the plant Kingdom, was chemically converted into ent-15α-hydroxy-kaur-16-en-19-oic acid (1). Substrate 1 was subjected to biotransformation by the fungus Fusarium proliferatum, furnishing a new derivative, ent-2α,15α-dihydroxy-kaur-16-en-19-oic acid (2). The structure of metabolite 2 was deduced on the basis of spectroscopy and MS data. Derivative 2 showed allelopathic activity on germination and growth of root and stem of lettuce (Lactuca sativa), inhibiting 100% of germination and growth of roots and stem, at higher concentration assayed (10?4?mol/L).

DITERPENE GLYCOSIDES FROM SENECIO RUFUS

Two new diterpene glycosides, named rufusoside A and B were isolated from Senecio rufus.Their structures have been established as ent-15α-(α-L-arabinopyranosyloxyl)-kaur-16-en-19-oic acid and ent-15α-(α-L-arabinopyranosyloxyl)-kaur-16-en-19-oic acid-β-D-glucopyranosyl ester, respectively, mainly through interpretation of their spectroscopic data.Key Word Index - Senecio rufus; Compositae; Rufusoside A and B; diterpenoid; glycoside; aglycone.

Ent-Kaurene Glycosides from Ageratina cylindrica

The aqueous extract of the leaves of Ageratina cylindrica afforded six new ent-kaurenoic acid glycosides together with the known diterpenoid paniculoside V, the flavonoid astragalin, chlorogenic acid, and l-chiro-inositol. The structures were elucidated mainly by NMR and MS methods, and the absolute configuration was established by vibrational circular dichroism spectroscopy. The new compounds showed moderate antiprotozoal activity against Entamoeba histolytica and Giardia lamblia trophozoites.

Synthesis, in vitro antimalarial activity and in silico studies of hybrid kauranoid 1,2,3-Triazoles Derived from Naturally Occurring Diterpenes

We herein report the synthesis of hybrid kauranoid molecules of type 1,2,3-triazole-1,4-disubstituted aiming to improve the antimalarial activity of kaurenoic and xylopic acids. The CuI-catalyzed cycloaddition of azides and kauranoid terminal a

Discovery and structure-activity relationships of ent-Kaurene diterpenoids as potent and selective 11β-HSD1 inhibitors: Potential impact in diabetes

The biological screening of a collection of nature occurring diterpenoids against 11β-HSD1 resulted in the discovery of the lead compound 1b, which pointed to the therapeutic potential for type 2 diabetes. Subsequently, an optimization project was initiated. Starting from compound 1b and its counterpart 2, the hemi-synthesis was performed on kaurenic acid scaffolds yielding 36 derivatives. Further evaluations on both human and mouse 11β-HSD revealed that seven urea derivatives exhibited significant improved potency and selectivity. Especially, the urea 19a has an IC50 (human 11β-HSD1) = 9.4 nM and selectivity index (human 11β-HSD) > 10,649. The 2D and 3D binding models of the complex 19a/11β-HSD1 were generated using docking simulations. Based on the results, the structural-activity relationships (SARs) of compounds 1b and 2 were also discussed.

Cytotoxic and apoptosis-inducing effect of ent-15-oxo-kaur-16-en-19-oic acid, a derivative of grandiflorolic acid from Espeletia schultzii

ent-Kaurenic acid and many natural derivatives of this diterpene are known to have interesting biological properties. ent-15-Oxo-kaur-16-en-19-oic acid can be easily obtained from grandiflorolic acid which was first isolated from Espeletia grandiflora. The present work describes the proapoptotic effect of ent-15-oxo-kaur-16-en-19-oic acid on the human prostate carcinoma epithelial cell line PC-3 as evidenced by the changes in the expression level of proteins associated with the execution and regulation of apoptosis. Cell viability was affected upon exposure to the compound, the IC50 were determined as 3.7 μg/ml, which is 4 times lower than that corresponding to a primary cell culture of fibroblasts (14.8 μg/mL). Through Western blot analysis, active forms of caspace-3 associated with the specific proteolysis of Poly(ADP-ribose) polymerase (PARP) were detected. Reduced levels of the antiapoptotic protein Bcl-2, as well as the appearance of internucleosomal DNA fragmentation, were also demonstrated. Thus, ent-15-oxo-kaur-16-en-19-oic acid may be a promising lead compound for new chemopreventive strategies, alone or in combination with traditional chemotherapy agents to overcome drug resistance in tumoral cells.

Ent-kaurenic Acid and Its Related Compounds from Glandular Trichome Exudate and Leaf Extracts of Polymnia sonchifolia

Yacon (Polymnia sonchifolia) leaves possess glandular trichomes on the surface.The exudate from the glandular trichome and the leaf are itself rich in ent-kaurenic acid (ent-kaur-16-en-19-oic acid).A kaurene derivative, 15-α-angeloyloxy-ent-kauren-19-oic