Mosquitocidal triterpenes from the stem of Duranta repens

Figures & data

Table 1.  ¹H-NMR (500 MHz, CDCl₃) and ¹³C-NMR (125 MHz, CDCl₃ ) data of compound 1.

H/C	Proton value ^δH		Carbon value ^δC		Long range coupling
	1a	1b	1a	1b	1a		1b
					^2J	^3J	^2J	^3J
1			38.2	38.5
2			28.8	28.8
3	3.23 (m)	3.27 (m)	80.6	80.5		23,24		23,24
4			40.3	40.2
5	2.21 (1H,brd,J= 10.6Hz)	0.74 (1H,br d, J = 11.0)	56.8	54.2	4	25		25
6			19.9	19.2
7			33.9	33.3
8			40.3	40.4
9	1.50~1.60 (m)	1.55 (1H, m)	49.1	49.2	11,8	26	11	26
10			38.5	35.4
11	1.89 (m)	1.92 (1H, m)	24.8	24.6	12		12	13
12	5.30 (1H,t, J= 3.6Hz)	5.26 (1H, t, J = 3.6Hz)	124.2	127.4		14	13	14
13			145.1	145.1
14			40.2	39.3
15			25.7	25.0
16			29.6	29.2
17			34.5	38.6
18	2.01 (1H,dd, J=5.0 & 15.0 Hz)	2.19 (1H,bd,J= 10.6Hz)	49.5	42.7	13	12	13	12,20
19			47.4	47.4
20			32.1	32.2
21		3.27* (m)	35.5	80.2			20
22		1.62 (2H,bd,J=10.0 Hz)	35.4	44.2				18
23	0.79, s, 3H	0.80, s, 3H	29.7	18.5		3		3
24	0.77, s, 3H	1.01, s, 3H	17.0	29.6		3,5		3,5
25	0.91, s, 3H	0.96, s, 3H	17.1	17.1		5		5
26	0.92, s, 3H	0.99, s, 3H	18.5	16.9		9,14		9,14
27	0.86, s, 3H	1.15, s, 3H	25.1	25.2	14	15		13
28	0.88, s, 3H	0.89, s, 3H	29.7	22.7		16		22
29	0.79, s, 3H	1.09, s, 3H	33.7	27.4		21		19
30	0.94, s, 3H	0.92, s, 3H	22.7	34.6		19,21		21

*overlap; 1a, β-Amyrin; 1b, 12-Oleanene 3, 21-diol.

Figure 1.  Structure of compound 1.

Table 2.  Larvicidal action of compound 1 from D. repens on C. quinquefasciatus at different instars.

Larval instar	Exposure period (h)	LC50 values (ppm)	95% fiducial limits (lower-upper)	χ^2 value (d.f.)
First	3	32.58	14.35–73.96	6.4
	6	12.32	5.06–29.98	5.37
	12	7.75	2.75–21.84	0.13
Second	12	49.29	17.86–136.01	2.83
	24	16.11	8.33–31.13	0.3
Third	12	65.82	19.96–217	6.01
	24	28.63	13.07–62.7	0.19
Fourth	12	82.96	14.17–485.64	0.23
	24	26.53	16.22–43.41	0.47

Values were based on four concentrations and three replications with 25 insects each.

d.f = degree of freedom.