Isogloiosiphone B, a novel acetal, and hydrophobic compounds as β-glucuronidase inhibitors derived from the red alga Neodilsea yendoana

Figures & data

Table 1. ¹H (500 MHz) and ¹³C NMR (125 MHz) data of compound 1 and literature data [21] of gloiosiphone B (5).

Position	Compound 1^a		Gloiosiphone B (5)^b
	δC	δH (mult, J in Hz)	δC	δH (mult, J in Hz)
2	101.9		96.0
3	211.7		208.8
4	36.3	2.55 (2H, m)	34.2	2.88 (2H, m)
5	64.2	4.33 (1H, m)	62.5	4.32 (1H, m)
		4.27(1H, m)		4.33 (1H, m)
6	63.1	3.62 (2H, d, 5.7)	72.8	3.62 (1H, d)
				3.90 (1H, d)
−OCH3	50.6	3.12 (3H, s)	59.9	3.45 (3H, s)
−OH		3.87 (1H, t, 5.7)		3.40 (1H, s)

^a measured in acetone-d₆.

^b measured in chloroform-d.

Figure 1. Compounds 1–4 isolated from N. yendoana as β-glucuronidase inhibitors and gloiosiphone B (5).

Table 2. β-Glucuronidase inhibitory activities of compounds 1–4.

Compound	IC50 (μM)	Ki (μM)	Inhibition mode
1	57.0 ± 0.56	8.3 ± 1.3	Competitive
2	103.7 ± 1.02	210.7 ± 13.7	Competitive
3	> 250	421.2 ± 7.1	Competitive
4	89.5 ± 0.44	32.7 ± 5.5	Non-competitive
D-Glucaro-1,4-lactone	77.9 ± 1.40	2.5 ± 2.1	Competitive

Chen JL, Moghaddam MF, Gerwick WH. Gloiosiphones A and B, novel metabolites from the red marine alga Gloiosiphonia verticillaris. J Nat Prod. 1993;56(8):1205–1210.10.1021/np50098a001

 Web of Science ®Google Scholar