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A new cyclopeptide from Dianthus caryophyllus
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Chinese Chemical Letters 19 (2008) 193–195 www.elsevier.com/locate/cclet
A new cyclopeptide from Dianthus caryophyllus Fei Li, Feng Mei Zhang, Ya Bin Yang, Xue Qiong Yang, Qiu E. Cao, Zhong Tao Ding * Key Laboratory of Medicinal Chemistry for Nature Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, # 2 Green Lake North Road, Kunming 650091, China Received 19 September 2007
Abstract A new cyclopeptide as well as a known cyclopeptide were isolated from the whole plants of Dianthus caryophyllus. Their structures were elucidated as cyclo (-Thr-Gly-Pro-Tyr-Phe-) (1) and cyclo (-Ala-Gly-Ser-IIe-Phe-Phe-) (2) by means of chemical and spectroscopic methods including MS, 1D and 2D NMR techniques. # 2007 Zhong Tao Ding. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. Keywords: Caryophyllaceae; Dianthus caryophyllus; Cyclopeptide; Caryophllusin A
Dianthus caryophyllus L. (Caryophyllaceae), a famous flower also called as carnation, is widely distributed all over the world [1]. There is no report about its cyclopeptide. As a series of investigation on Caryophyllaceae-type homocyclopeptides [2–6], from the ethanol extract, a new cyclopeptide named caryophllusin A (1) and a known cyclopeptide as cyclo (-Ala-Gly-Ser-IIe-Phe-Phe-) (2) [7] were isolated. In this paper, the isolation and structural elucidation of compound 1 were described. The air-dried whole plants of D. caryophyllus L. (16.5 kg) were extracted with 70% ethanol for three times. The concentrated extract was suspended in water, and then extracted with petroleum ether, ethyl acetate and n-BuOH, respectively. The n-BuOH residue (200.0 g) was subjected to SPD-100 column chromatography using H2O–MeOH gradient system (1:0–0:1). The fraction eluted with 50% MeOH was further subjected to silica gel column chromatograph, Pharmadex LH-20 and RP-18 to yield compound 1 (14 mg) and compound 2 (16 mg) as white powders. Caryophllusin A (1), ½a23 D 34.8 (c. 0.008, MeOH), was negative to ninhydrin reagent but positive after hydrolyzed with 6 mol/L HCl [8]. Based on the HR ESI-MS ([M + H]+ at m/z 566.6269; calcd. 566.6299), its molecular formula was established as C29H35N5O7, indicated 15 degrees of unsaturation. IR spectrum (KBr) exhibited intense N–H and C O absorption at 3300 and 1650 cm1, respectively. The 13C NMR and 1H NMR spectra showed the presence of five amide carbonyl signals in the range (d 173.1–178.5) and four NH signals in the range (d 7.38–8.61), respectively. The results mentioned above suggested 1 was a cyclopeptide. By analysis of 1H–1H COSY, HMBC and HMQC spectra, the amino acid residues consisted of compound 1 were proved to be one threonine, one tyrosine, one glycine, one phenylalanine and one proline, which were supported by standard amino acid analysis of the hydrolysate prepared from compound 1. These
* Corresponding author. E-mail address: [email protected] (Z.T. Ding). 1001-8417/$ – see front matter # 2007 Zhong Tao Ding. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. doi:10.1016/j.cclet.2007.12.010
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F. Li et al. / Chinese Chemical Letters 19 (2008) 193–195
Fig. 1. The structure of caryophllusin A, arrows show selected HMBC correlations (H ! C).
Table 1 1 H NMR (500 MHz) and CO
Ca
13
Cb
C (125 MHz) NMR data of caryophllusin A in pyridine-d5 (d ppm, J Hz) Cg
Cd
Thr 173.7 62.87 72.16 Gly 173.9 45.50
21.83
Pro
178.5 63.89 35.16
23.50 52.05
Tyr
177.7 59.13 38.16 128.7
Phe 173.1 60.67 37.32 142.4
HN
Ha
Hb
Hg
Hd
7.96(br.s) 7.99(br.s)
132.9, 118.7, 132.1, 128.9,
5.13(m) 5.18(m) 1.43(d, J = 7.7) 5.09(d, J = 18.6), 3.82(d, J = 18.6) 4.71(m) 2.06(m), 1.49(m) 3.77(m), 3.53(m) 1.92(m) 118.7, 160.2, 8.61(d, J = 6.7) 5.01(m) 3.21(m) 7.05 (br.s) 132.9 131.9, 7.38(br.s) 4.12(m) 3.89(m), 7.36(d, J = 7.4), 131.9, 132.1 3.46(m) 7.60(m), 7.08(d, J = 7.4)
amino acid residues accounted for the molecular weight observed in ESI-MS of 1. The sequence of amino acid residues for compound 1 was elucidated from the HMBC spectrum. HMBC spectrum exhibited the correlations between NHGly and C OThr, d-HPro and C OGly, NHTyr and C OPro, a-HPhe and C OTyr, respectively (Fig. 1). Therefore, the structure of compound 1 was established to be cyclo (-Thr-Gly-Pro-Tyr-Phe-). The complete assignments for the 1H and 13C NMR signal of compound 1 in pyridine-d5 were accomplished using a combination of 2D NMR experiments (Table 1). Up to now, about 170 Caryophyllaceae-type homocyclopeptides were obtained from plants. They mainly consisted of six to nine protein amino acids, only eight cyclopeptides consisting of five amino acids were obtained [9]. Acknowledgments This work was financially supported by the Natural Science Foundation of Ynunan Province (No. 2007B021M) and Yunnan University (No. 2003Q008A). References [1] C.L. Tang, P. Ke, D.Q. Lu, The Plant Index of China, vol. 2, Science Press, Beijing, 1996, p. 255. [2] M.H. Li, X.Q. Yang, Z.J. Wan, Y.B. Yang, F. Li, Z.T. Ding, Chin. J. Nat. Med. 5 (2007) 24.
F. Li et al. / Chinese Chemical Letters 19 (2008) 193–195 [3] [4] [5] [6] [7] [8] [9]
Z.T. Ding, J. Zhou, N.H. Tan, Y.X. Cheng, S.M. Deng, Acta Bot. Sin. 43 (2001) 541. Z.T. Ding, J. Zhou, N.H. Tan, R.W. Teng, Planta Med. 66 (2000) 386. Z.T. Ding, J. Zhou, Y.X. Cheng, N.H. Tan, Chin. Chem. Lett. 11 (2000) 593. Z.T. Ding, Y.C. Wang, J. Zhou, N.H. Tan, H.M. Wu, Chin. Chem. Lett. 10 (1999) 1037. H. Morita, T. Kayashita, A. Uchida, K. Takeya, J. Nat. Prod. 60 (1997) 212. J. Zhou, N.H. Tan, Chin. Sci. Bull. 45 (2000) 1825. N.H. Tan, J. Zhou, Chem. Rev. 106 (2006) 840.
195
Chinese Chemical Letters 19 (2008) 193–195 www.elsevier.com/locate/cclet
A new cyclopeptide from Dianthus caryophyllus Fei Li, Feng Mei Zhang, Ya Bin Yang, Xue Qiong Yang, Qiu E. Cao, Zhong Tao Ding * Key Laboratory of Medicinal Chemistry for Nature Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, # 2 Green Lake North Road, Kunming 650091, China Received 19 September 2007
Abstract A new cyclopeptide as well as a known cyclopeptide were isolated from the whole plants of Dianthus caryophyllus. Their structures were elucidated as cyclo (-Thr-Gly-Pro-Tyr-Phe-) (1) and cyclo (-Ala-Gly-Ser-IIe-Phe-Phe-) (2) by means of chemical and spectroscopic methods including MS, 1D and 2D NMR techniques. # 2007 Zhong Tao Ding. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. Keywords: Caryophyllaceae; Dianthus caryophyllus; Cyclopeptide; Caryophllusin A
Dianthus caryophyllus L. (Caryophyllaceae), a famous flower also called as carnation, is widely distributed all over the world [1]. There is no report about its cyclopeptide. As a series of investigation on Caryophyllaceae-type homocyclopeptides [2–6], from the ethanol extract, a new cyclopeptide named caryophllusin A (1) and a known cyclopeptide as cyclo (-Ala-Gly-Ser-IIe-Phe-Phe-) (2) [7] were isolated. In this paper, the isolation and structural elucidation of compound 1 were described. The air-dried whole plants of D. caryophyllus L. (16.5 kg) were extracted with 70% ethanol for three times. The concentrated extract was suspended in water, and then extracted with petroleum ether, ethyl acetate and n-BuOH, respectively. The n-BuOH residue (200.0 g) was subjected to SPD-100 column chromatography using H2O–MeOH gradient system (1:0–0:1). The fraction eluted with 50% MeOH was further subjected to silica gel column chromatograph, Pharmadex LH-20 and RP-18 to yield compound 1 (14 mg) and compound 2 (16 mg) as white powders. Caryophllusin A (1), ½a23 D 34.8 (c. 0.008, MeOH), was negative to ninhydrin reagent but positive after hydrolyzed with 6 mol/L HCl [8]. Based on the HR ESI-MS ([M + H]+ at m/z 566.6269; calcd. 566.6299), its molecular formula was established as C29H35N5O7, indicated 15 degrees of unsaturation. IR spectrum (KBr) exhibited intense N–H and C O absorption at 3300 and 1650 cm1, respectively. The 13C NMR and 1H NMR spectra showed the presence of five amide carbonyl signals in the range (d 173.1–178.5) and four NH signals in the range (d 7.38–8.61), respectively. The results mentioned above suggested 1 was a cyclopeptide. By analysis of 1H–1H COSY, HMBC and HMQC spectra, the amino acid residues consisted of compound 1 were proved to be one threonine, one tyrosine, one glycine, one phenylalanine and one proline, which were supported by standard amino acid analysis of the hydrolysate prepared from compound 1. These
* Corresponding author. E-mail address: [email protected] (Z.T. Ding). 1001-8417/$ – see front matter # 2007 Zhong Tao Ding. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. doi:10.1016/j.cclet.2007.12.010
194
F. Li et al. / Chinese Chemical Letters 19 (2008) 193–195
Fig. 1. The structure of caryophllusin A, arrows show selected HMBC correlations (H ! C).
Table 1 1 H NMR (500 MHz) and CO
Ca
13
Cb
C (125 MHz) NMR data of caryophllusin A in pyridine-d5 (d ppm, J Hz) Cg
Cd
Thr 173.7 62.87 72.16 Gly 173.9 45.50
21.83
Pro
178.5 63.89 35.16
23.50 52.05
Tyr
177.7 59.13 38.16 128.7
Phe 173.1 60.67 37.32 142.4
HN
Ha
Hb
Hg
Hd
7.96(br.s) 7.99(br.s)
132.9, 118.7, 132.1, 128.9,
5.13(m) 5.18(m) 1.43(d, J = 7.7) 5.09(d, J = 18.6), 3.82(d, J = 18.6) 4.71(m) 2.06(m), 1.49(m) 3.77(m), 3.53(m) 1.92(m) 118.7, 160.2, 8.61(d, J = 6.7) 5.01(m) 3.21(m) 7.05 (br.s) 132.9 131.9, 7.38(br.s) 4.12(m) 3.89(m), 7.36(d, J = 7.4), 131.9, 132.1 3.46(m) 7.60(m), 7.08(d, J = 7.4)
amino acid residues accounted for the molecular weight observed in ESI-MS of 1. The sequence of amino acid residues for compound 1 was elucidated from the HMBC spectrum. HMBC spectrum exhibited the correlations between NHGly and C OThr, d-HPro and C OGly, NHTyr and C OPro, a-HPhe and C OTyr, respectively (Fig. 1). Therefore, the structure of compound 1 was established to be cyclo (-Thr-Gly-Pro-Tyr-Phe-). The complete assignments for the 1H and 13C NMR signal of compound 1 in pyridine-d5 were accomplished using a combination of 2D NMR experiments (Table 1). Up to now, about 170 Caryophyllaceae-type homocyclopeptides were obtained from plants. They mainly consisted of six to nine protein amino acids, only eight cyclopeptides consisting of five amino acids were obtained [9]. Acknowledgments This work was financially supported by the Natural Science Foundation of Ynunan Province (No. 2007B021M) and Yunnan University (No. 2003Q008A). References [1] C.L. Tang, P. Ke, D.Q. Lu, The Plant Index of China, vol. 2, Science Press, Beijing, 1996, p. 255. [2] M.H. Li, X.Q. Yang, Z.J. Wan, Y.B. Yang, F. Li, Z.T. Ding, Chin. J. Nat. Med. 5 (2007) 24.
F. Li et al. / Chinese Chemical Letters 19 (2008) 193–195 [3] [4] [5] [6] [7] [8] [9]
Z.T. Ding, J. Zhou, N.H. Tan, Y.X. Cheng, S.M. Deng, Acta Bot. Sin. 43 (2001) 541. Z.T. Ding, J. Zhou, N.H. Tan, R.W. Teng, Planta Med. 66 (2000) 386. Z.T. Ding, J. Zhou, Y.X. Cheng, N.H. Tan, Chin. Chem. Lett. 11 (2000) 593. Z.T. Ding, Y.C. Wang, J. Zhou, N.H. Tan, H.M. Wu, Chin. Chem. Lett. 10 (1999) 1037. H. Morita, T. Kayashita, A. Uchida, K. Takeya, J. Nat. Prod. 60 (1997) 212. J. Zhou, N.H. Tan, Chin. Sci. Bull. 45 (2000) 1825. N.H. Tan, J. Zhou, Chem. Rev. 106 (2006) 840.
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