Syntheses and biological activities of the proposed structure of apteniol A and its derivatives

Figures & data

Table 1. NMR Data of 1 and reported apteniol A (in CD₃OD).

No.	1^a		Ref. 1^a		Ref. 3^b
	^13C	^1H(J in Hz)	^13C	^1H(J in Hz)	^13C	^1H(J in Hz)
1	137.1		129.6		132.5
2,6	130.7	7.16 d (8.6)	130.7	6.92 d (8.5)	115.4	7.07 d (8.4)
3,5	119.7	6.89 d (8.6)	116.6	6.63 d (8.5)	129.5	6.75 d (8.4)
4	157.3		157.4		154.1
7	31.3	2.88 t (7.6)	35.7	2.84 t (8.1)	29.9	2.89 t (7.5)
8	36.8	2.58 t (7.6)	42.9	2.66 t (8.1)	34.5	2.64 t (7.5)
9	176.7		180.6		n.d.

^{a 13}C-NMR:125 MHz, ¹H-NMR:500 MHz.

^{b 13}C-NMR:75 MHz, ¹H-NMR:300 MHz (solvent was unknown).

Table 2. Effect of compound 1 on germination of L. sativa.

	Germination rate (%)	Root length (mm)
Control	91	173 ± 54.2
Compound 1 (0.1 µM)	91	302 ± 67.8

Germination data were arcsine transformed and analyzed using student’s t-test, at a significance level of p < 0.05.

Fig. 1. Biological assay.

Notes: (A) Effects of proposed apteniol A and its derivatives on Bt₂cAMP-induced neurite outgrowth in PC12 cells. PC12 cells were plated at 4.0 × 10³ cells/well and cultured with indicated test compound concentrations in the presence of 0.5 mM Bt₂cAMP. The extent of neurite outgrowth was measured after 24 h and expressed as the mean percentage of 300–400 cells from triplicate cultures. The bars represent SD. **p < 0.01 (Dunnett’s test) compared with the control (Bt₂cAMP 0.5 mM only). (B) Inhibitory effects of proposed apteniol A and its derivatives on antigen-induced degranulation in RBL-2H3 cells. DNP-IgE sensitized RBL-2H3 cells were incubated with indicated test compound concentrations for 20 min and stimulated with DNP-HAS for 1 h. Released β-hexosaminidase was measured. Data correspond to means of triplicate cultures and the bars represent SD. *p < 0.05, **p < 0.01 (Dunnett’s test) compared with control.

Scheme 1. Synthesis of proposed apteniol A and its derivatives.

Notes: Reagents and conditions: (a) CuI, N,N-dimethylglycine HCl salt, Cs₂CO₃, DMF, 100 °C (82%); (b) triethyl phosphonoacetate, NaH, benzene, rt (96%); (c) Pd/C, H₂, MeOH, 50 °C (98%); (d) NaOH, THF/H₂O, rt (62%); (e) H₂SO_4, MeOH, reflux (90%); (f) methylamine (40% in methanol), NaH, 100 °C (40%).

DellaGreca M, Di Marino C, Previtera L, Purcaro R, Zerrelli A. Apteniols A–F, oxyneolignans from the leaves of Aptenia cordifolia. Tetrahedron. 2005;61:11924–11929.10.1016/j.tet.2005.09.054

 Web of Science ®Google Scholar

Devi P, Wahidullah S, Rodrigues C, Souza LD. The sponge-associated bacterium Bacillus licheniformis SAB1: a source of antimicrobial compounds. Mar. Drugs. 2010;8:1203–1212.10.3390/md8041203

 PubMed Web of Science ®Google Scholar