Supplementary Information
Low-toxicity diindol-3-ylmethanes as potent antifouling compounds
Kai-Ling Wanga,b, #, Ying Xub,d, #, Liang Luc, Yong-Xin Lib, Zhuang Hanb,e, Jun
Zhangf, Chang-Lun Shaoa, Chang-Yun Wanga, *, Pei-Yuan Qianb,c, *
a
Key Laboratory of Marine Drugs, The Ministry of Education of China, School of
Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, China
b
Division of Life Science, Hong Kong University of Science and Technology, Clear
Water Bay, Hong Kong SAR, China
c
Environmental Science Program, School of Science, Hong Kong University of
Science and Technology, Clear Water Bay, Hong Kong SAR, China
d
College of Life Science, Shenzhen University, 3688 Nanhai Ave, Shenzhen, 518060,
China
e
Sanya Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences,
62 Fenghuang Road, Sanya, 572000, China
f
College of Pharmacy, Jinan University, Guangzhou, 510632, China
#: Co-first authors
*: Co-corresponding authors
Authors to whom correspondence should be addressed. Pei-Yuan Qian. Tel.: 0852-235
8-7331; Fax: 0852-2358-1559; email: boqianpy@ust.hk; Chang-Yun Wang, Tel.: 86-5
32-82031536; Fax: 86-532-82031536; email: changyun@ ouc.edu.cn.
1
Contents
Fig. S1 Chemical structures, detailed 1H NMR chemical shifts and UPLC-MS
mass spectra data for chemical standard di(1H-indol-3-yl)methane (DIM) and
compounds 1–8a
Fig. S2 UPLC profiles of the single injections of isolated and purchased DIM as
well as the co-injection of these two samples
Fig. S3 1H-NMR spectra and UPLC-MS chromatographic data for chemical
standard DIM and compounds 1–8a
Note to that chemical standard di(1H-indol-3-yl)methane (DIM) was purchased from
Sigma Chemical (Sigma Chemical Co., St Louis, MO, USA). Commercial source
information is as follows: Chemical Name: 3,3'-Diindolylmethane; Synonyms: DIM;
Order Number: D9568; Grade: ≥98% (HPLC); Quantity: 5 g; Bulk Available; Stock
Status: Maintained in stock; Quantity Category: Grams.
2
Fig. S1 Chemical structures, detailed 1H NMR chemical shifts and UPLC-MS
mass spectra data for chemical standard di(1H-indol-3-yl)methane (DIM) and
compounds 1–8a
H
N
N
H
Chemical standard: di(1H-indol-3-yl)methane, slightly pink powder;
1
H NMR
(500MHZ; DMSO-d6) 10.73 (br s, 2 NH, H-1′, 1′′), 7.51 (d, J = 7.9 Hz, 2H, H-4′,4′′),
7.31 (d, J = 8.1 Hz, 2H, H-7′, 7′′), 7.13 (d, J = 2.3 Hz, 2H, H-2′, 2′′), 7.02 (td, J = 7.1,
1.0 Hz, 2 H, H-6′,6′′), 6.91 (td, J = 7.1, 0.8 Hz, 2H, H-5′, 5′′), 4.12(s, 2H, CH2), ppm;
ESIMS m/z 247.1266 [M + H]+ (calcd for C17H15N2, 247.1235).
H
N
N
H
1
di(1H-indol-3-yl)methane (1): slightly pink powder; 1H NMR (500MHZ; DMSO-d6)
10.73 (br s, 2 NH, H-1′, 1′′), 7.52 (d, J = 8.9 Hz, 2H, H-4′,4′′), 7.31 (d, J = 8.1 Hz, 2H,
H-7′, 7′′), 7.13 (d, J = 2.2 Hz, 2H, H-2′, 2′′), 7.03 (td, J = 7.1, 1.0 Hz, 2H, H-6′, 6′′),
6.91 (td, J = 6.9, 0.2 Hz, 2 H, H-5′,5′′), 4.12(s, 2H, CH2) ppm; ESIMS m/z 247.1266
[M + H]+ (calcd for C17H15N2, 247.1235).
3
H
N
N
H
2
Vibrindole A (2): yellowish oil; 1H NMR (500MHZ; DMSO-d6) 10.70 (br s, 2NH,
H-1′, 1′′), 7.42 (d, J = 8.0 Hz, 2H, H-4′,4′′), 7.29 (d, J = 9.1 Hz, 2H, H-7′, 7′′), 7.13 (d,
J = 1.9 Hz, 2H, H-2′, 2′′), 6.98 (td, J = 7.9, 0.8 Hz, 2H, H-6′,6′′), 6.84 (td, J = 7.8, 0.7
Hz, 2H, H-5′, 5′′), 4.54 (q, J = 7.1Hz, 1H, H-1), 1.73 (d, J = 7.2 Hz, 3H, H-2) ppm;
ESIMS m/z 261.1351 [M + H]+ (calcd for C18H17N2, 261.1392).
H
N
OH
OH
N
H
3
3,3'-di-1H-indol-3-yl-1,2-propandiol (3): pale yellow oil; IH NMR (500MHZ;
DMSO-d6) 10.73 (br s, 2 NH, H-1′, 1′′), 7.53 (d, J = 7.2 Hz, 1 H, H-4′), 7.52 (d, J =
7.6 Hz, 1 H, H-4′′), 7.31 (d, J = 2.2 Hz, 1 H, H-2′), 7.29 (d, J = 8.2 Hz, 2 H, H-7′, 7′′),
7.13 (d, J = 2.0 Hz, 1 H, H-2′′), 6.99 (dq, J = 9.9, 1.0 Hz, 2 H, H-6′, 6′′), 6.87 (td, J =
7.9 Hz, 0.9 Hz, 1 H, H-5′), 6.85 (td, J = 8.9 Hz, 0.9 Hz, 1 H, H-5′′), 4.58 (d, J = 5.9
Hz 1H, H-1), 4.27 (q, J = 11.4, 5.0 Hz, 1H, H-2)，3.17 (d, J = 5.0 Hz, 2 H, H-3) ppm;
ESIMS m/z 307.1451 [M + H]+ (calcd for C19H19N2O2, 307.1447).
4
H
N
NH
N
H
4
tri(1H-indol-3-yl)methane (4): red powder; IH NMR (500MHZ; DMSO-d6) 10.71
(br s, 3 NH, H-1′, 1′′, 1′′′), 7.37 (d, J = 8.0 Hz, 3 H, H-4′,4′′, 4′′′), 7.31 (d, J = 8.1 Hz,
3 H, H-7′, 7′′, 7′′′), 6.99 (td, J = 7.1, 0.1 Hz, 3 H, H-6′, 6′′,6′′′), 6.92 (d, J = 2.0 Hz, 3
H, H-2′, 2′′, 2′′′), 6.83 (td, J = 7.9, 0.9 Hz, 3 H, H-5′, 5′′, 5′′′), 6.03 (s, 1H, H-1) ppm;
ESIMS m/z 362.1646 [M + H]+ (calcd for C25H20N3, 362.1657).
H
N
NH
O
N
H
5
1,2,2-tri(1H-indol-3-yl) ethanone (5): slightly red powder; IH NMR (500MHZ;
DMSO-d6) 11.94 (s, 1 NH, H-1′′′), 10.83 (br s, 2 NH, H-1′, 1′′), 8.73 (s, 1 H, H-2′′′),
8.20 (d, J = 7.7 Hz, 1 H, 4′′′), 7.66 (d, J = 8.0 Hz, 2 H, H-4′,4′′), 7.44 (d, J = 7.9 Hz, 1
H, H-7′′′), 7.31 (d, J = 8.1 Hz, 2 H, H-7′, 7′′), 7.24 (d, J = 2.2 Hz, 2 H, H-2′, 2′′), 7.17
(td, J = 8.2, 1.3 Hz, 1 H, H-6′′′), 7.13 (td, J = 7.6, 1.0 Hz, 1 H, H-5′′′), 7.01 (td, J = 7.9,
0.6 Hz, 2 H, H-5′, 5′′), , 6.91 (td, J = 7.8, 0.6 Hz, 2 H, H-6′, 6′′), 6.41 (s, 1H, H-1) ppm;
ESIMS m/z 390.1648 [M + H]+ (calcd for C26H20N3O, 390.1606).
5
H
N
N
N
H
6
Arsindoline A (6): colorless amorphous powder; IH NMR (500MHZ; DMSO-d6)
10.90 (br s, 2 NH, H-1′, 1′′), 8.75 (d, J = 4.5 Hz, 1H, H-2′′′), 8.32 (d, 1H, J = 8.5 Hz,
H-8′′′), 8.03 (d, J = 7.9 Hz, 1H, H-5′′′), 7.70 (td, 1H, J = 8.2 Hz, J′ = 1.2 Hz, H-7′′′),
7.52 (td, 1H, J = 8.2 Hz, J′ = 1.5 Hz, H-6′′′), 7.38 (d, J = 8.2 Hz, 2 H, H-4′,4′′), 7.29 (d,
J = 8.0 Hz, 2 H, H-7′, 7′′), 7.20 (d, J = 4.5 Hz, 1H, H-3′′′), 7.04 (td, J = 8.0, J′ = 0.8
Hz, 2 H, H-6′, 6′′), 6.86 (td, J = 8.0, J′ = 0.8 Hz, 2 H, H-5′, 5′′), 6.82 (d, J = 2.0 Hz, 2
H, H-2′, 2′′), 6.68 (s, 1H, H-1) ppm; ESIMS m/z 374.1653 [M + H]+ (calcd for
C26H20N3, 374.1657).
H
N
N
H
7
3,3'-(phenylmethylene)bis-1H-indole (7): pale pink powder; IH NMR (500MHZ;
DMSO-d6) 10.81 (br s, 2 NH, H-1′, 1′′), 7.37–7.33 (m, 4H, H-4′,4′′, 7′, 7′′), 7.28–7.25
(m, 4H, H-2′′′, 3′′′, 5′′′, 6′′′), 7.03 (td, 1H, J = 8.0, 1.1 Hz, 2H, H-6′, 6′′), 6.85 (td, 1H,
J = 7.9, 0.8 Hz, 2H, H-5′, 5′′), 6.77 (d, J = 2.1 Hz, 2 H, H-2′, 2′′), 5.69 (s, 1H, H-1)
ppm; ESIMS m/z 323.1547 [M + H]+ (calcd for C23H19N2, 323.1548).
6
H
N
OH
N
H
8
4-(di(1H-indol-3-yl)methyl) phenol (8): bright red powder; IH NMR (500MHZ;
DMSO-d6) 10.76 (br s, 2 NH, H-1′, 1′′), 9.14 (s, 1H, OH), 7.32 (d, J = 8.2 Hz, 2 H,
H-4′,4′′), 7.25 (d, J = 8.1 Hz, 2 H, H-7′, 7′′), 7.12 (d, J = 8.5 Hz, 2H, H-2′′′, 6′′′), 7.01
(td, 1H, J = 8.0, 0.8 Hz, 2H, H-6′, 6′′), 6.84 (td, 1H, J = 7.7, 0.5 Hz, 2H, H-5′, 5′′),
6.77 (d, J = 2.1 Hz, 2 H, H-2′, 2′′), 6.65 (d, J = 8.5 Hz, 1H, H-3′′′, 5′′′), 5.69 (s, 1H,
H-1) ppm; ESIMS m/z 339.1531 [M + H]+ (calcd for C23H19N2O, 339.1497).
H
N
OAc
N
H
8a
4-[di(1H-indol-3-yl)methyl] phenyl acetate (8a): red amorphous powder; 1H NMR
(CDCl3, 300MHZ, δ ppm) 7.94 (br s, 2 NH, H-1′, 1′′), 7.39–7.31 (m, 6 H, H-4′, 7′, 4′′,
7′′, 2′′′, 6′′′), 7.19–7.14 (m, 2H, H-3′′′, 5′′′), 7.03–6.98 (m, 6 H, H-5′, 6′, 5′′, 6′′), 6.67
(s, 2H, H-2′, 2′′), 5.89 (s, 1H, H-1), 2.28 (s, 3 H, CH3) ppm; ESIMS m/z 381.1899 [M
+ H]+ (calcd for C25H20N2O2, 381.1603).
7
Fig. S2 UPLC profiles of the single injections of isolated and purchased DIM as
well as the co-injection of these two samples
8
Fig. S3 1H-NMR spectrum and UPLC-MS chromatographic data for chemical
standard DIM and compounds 1–8a
(A) Chemical standard: commercial DIM
9
(B) di(1H-indol-3-yl)methane (1)
10
(C) Vibrindole A (2)
11
(D) 3,3'-di-1H-indol-3-yl-1,2-propandiol (3)
12
(E) tri(1H-indol-3-yl)methane (4)
13
(F) 1,2,2-Tri(1H-indol-3-yl) ethanone (5)
14
(G) Arsindoline A (6)
15
(H) 3,3'-(phenylmethylene) bis-1H-indole (7)
16
(I) 4-(di(1H-indol-3-yl)methyl) phenol (8)
17
(J) 4-(di(1H-indol-3-yl)methyl) phenyl acetate (8a)
18