化合物1:无色结晶固体,茚三酮显色阴性。HRESIMS给出准分子离子峰m/z 768.4661 [M+H]+ (calcd 768.4660),确定其分子量为767。结合1H和13C-NMR谱确定其分子式为C40H61N7O8,计算不饱和度为14。1D NMR谱图给出典型的肽类化合物特征信号。其中,1H NMR谱显示有5个低场区的酰胺氨基质子信号(δH 9.45, 8.90, 8.71, 7.23, 7.16),7个α-次甲基质子信号(δH 4.69, 4.32, 4.16, 4.12, 4.03, 3.89, 3.51)。13C NMR谱提示有7个酰胺羰基碳信号(δC 171.6, 171.1, 170.9, 170.8, 170.6, 169.6, 168.5),7个α-次甲基碳信号(δC 60.7, 60.6, 59.2, 55.4, 55.1, 55.0, 54.1)。由此推断该化合物可能为七肽。结合2D NMR谱图,确定该七肽由两个脯氨酸残基、一个亮氨酸残基、两个异亮氨酸残基、一个苯丙氨酸残基和一个丝氨酸残基组成。残基连接顺序由HMBC、ROESY相关信号和ESI-MS/MS质谱数据确定,绝对构型由高级Marfey法确定[7-8]。综上,该化合物结构为cyclo-(L-Pro-L-Ser-L-Phe-L-Ile-L-Leu-L-Pro-L-Ile)。将核磁共振数据归属如下:1H NMR (700 MHz, DMSO-d6) δH 9.45 (1H, d, J = 8.4 Hz, 36-NH), 8.90 (1H, br s, 7-NH), 8.71 (1H, d, J = 6.6 Hz, 25-NH), 7.23 (1H, d, J = 10.3 Hz, 19-NH), 7.16 (1H, d, J = 4.8 Hz, 10-NH), 7.31 (2H, d, J = 7.5 Hz, H-13, H-17), 7.25 (2H, t, J = 7.5 Hz, H-14, H-16), 7.20 (1H, t, J = 7.3 Hz, H-15), 4.69 (1H, d, J = 7.8 Hz, H-2), 4.39 (1H, m, H-34a), 4.32 (1H, dd, J = 11.0, 8.4 Hz, H-36), 4.16 (1H, m, H-10), 4.12 (1H, t, J = 10.5 Hz, H-19), 4.03 (1H, t, J = 7.8 Hz, H-31), 3.89 (1H, t, J = 7.1 Hz, H-7), 3.57 (1H, m, H-34b), 3.51 (1H, m, H-25), 3.50 (1H, m, H-5a), 3.49 (1H, m, H-8a), 3.47 (1H, m, H-8b), 3.36 (1H, m, H-5b), 3.13 (1H, dd, J = 13.1, 2.8 Hz, H-11a), 2.84 (1H, dd, J = 13.0, 9.5 Hz, H-11b), 2.38 (1H, m, H-3a), 2.18 (1H, td, J = 12.7, 4.3 Hz, H-26a), 2.08 (1H, m, H-32a), 2.05 (1H, m, H-37), 2.01 (1H, m, H-33a), 1.92 (1H, m, H-3b), 1.90 (1H, m, H-4a), 1.79 (1H, m, H-33b), 1.73 (1H, m, H-32b), 1.55 (1H, m, H-26b), 1.53 (1H, m, H-39a), 1.52 (1H, m, H-4b), 1.43 (1H, m, H-20), 1.42 (2H, m, H-22a, H-27), 1.15 (1H, m, H-39b), 1.09 (1H, m, H-22b), 0.87 (3H, m, H-21), 0.85 (3H, m, H-29), 0.83 (6H, m, H-23, H-38), 0.82 (3H, m, H-28), 0.75 (3H, t, J = 7.3 Hz, H-40);13C NMR (175 MHz, DMSO-d6) δC 171.6 (C-30), 171.1 (C-35), 170.9 (C-9), 170.8 (C-1), 170.6 (C-24), 169.6 (C-18), 168.5 (C-6), 136.9 (C-12), 129.9 (C-13, C-17), 127.9 (C-14, C-16), 126.4 (C-15), 60.7 (C-31), 60.6 (C-2, C-8), 59.2 (C-19), 55.4 (C-7), 55.1 (C-10), 55.0 (C-36), 54.1 (C-25), 48.2 (C-34), 46.3 (C-5), 37.0 (C-11, C-26), 36.7 (C-20), 34.8 (C-37), 30.8 (C-3), 29.4 (C-32), 24.7 (C-27, C-33), 24.2 (C-22), 23.9 (C-39), 23.2 (C-29), 22.2 (C-4), 20.8 (C-28), 14.9 (C-40), 14.5 (C-23), 10.1 (C-38), 9.5 (C-21)。以上数据与文献[9]基本一致,故将化合物1鉴定为stylopeptide 1。
化合物2:无色无定形粉末,茚三酮显色阴性。HRESIMS给出准分子离子峰m/z 770.4102 [M+H]+ (calcd 770.4089),确定其分子量为769。结合1H和13C-NMR谱确定其分子式为C38H55N7O10,计算不饱和度为15。1D NMR谱图给出典型的肽类化合物特征信号。其中,1H NMR谱显示有5个低场区的酰胺氨基质子信号(δH 8.77, 8.43, 8.33, 8.03, 7.55),7个α-次甲基质子信号(δH 4.53, 4.38, 4.34, 4.28, 4.05, 4.03, 3.99)。13C NMR谱提示有7个酰胺羰基碳信号(δC 172.6, 172.4, 170.6, 170.5, 170.3, 170.0, 169.9),7个α-次甲基碳信号(δC 62.5, 60.4, 57.5, 56.9, 51.6, 49.9, 47.4)。据此推断该化合物可能为七肽。结合2D NMR谱图,确定该七肽由两个脯氨酸残基、一个亮氨酸残基、一个酪氨酸残基、一个天冬氨酸残基、一个丙氨酸残基和一个异亮氨酸残基组成。残基连接顺序由HMBC、ROESY相关信号和ESI-MS/MS质谱数据确定,绝对构型由高级Marfey法确定。综上,该化合物结构为cyclo-(L-Pro-L-Asp-L-Tyr-L-Pro-L-Ile-L-Ala-L-Leu)。将核磁共振数据归属如下:1H NMR (700 MHz, DMSO-d6) δH 8.77 (1H, br s, 31-NH), 8.43 (1H, d, J = 7.5 Hz, 11-NH), 8.33 (1H, br s, 25-NH), 8.03 (1H, s, 7-NH), 7.55 (1H, d, J = 6.5 Hz, 34-NH), 6.97 (2H, d, J = 8.1 Hz, H-14, H-18), 6.66 (2H, d, J = 8.1 Hz, H-15, H-17), 4.53 (1H, m, H-7), 4.38 (1H, m, H-31), 4.34 (1H, m, H-20), 4.28 (1H, d, J = 7.5 Hz, H-34), 4.05 (1H, m, H-11), 4.03 (1H, m, H-2), 3.99 (1H, m, H-25), 3.63 (1H, m, H-5a), 3.56 (1H, m, H-5b), 3.26 (2H, m, H-8a, H-23a), 2.99 (1H, m, H-12a), 2.88 (1H, m, H-12b), 2.83 (1H, m, H-8b), 2.59 (1H, m, H-23b), 2.22 (1H, m, H-3a), 2.10 (1H, m, H-21a), 1.87 (1H, m, H-4a), 1.77 (1H, m, H-4b), 1.68 (1H, m, H-35a), 1.67 (2H, m, H-21b, H-26), 1.58 (1H, m, H-35b), 1.57 (1H, m, H-3b), 1.55 (1H, m, H-36), 1.54 (1H, m, H-22a), 1.53 (1H, m, H-28a), 1.24 (1H, m, H-22b), 1.16 (3H, d, J = 6.6 Hz, H-32), 1.10 (1H, m, H-28b), 0.86 (3H, d, J = 5.8 Hz, H-37), 0.82 (3H, m, H-38), 0.80 (6H, m, H-27, H-29); 13C NMR (175 MHz, DMSO-d6) δC 172.6 (C-1), 172.4 (C-24), 172.1 (C-9), 170.6 (C-19), 170.5 (C-10), 170.3 (C-6), 170.0 (C-33), 169.9 (C-30), 155.9 (C-16), 129.6 (C-14, C-18), 127.8 (C-13), 115.1 (C-15, C-17), 62.5 (C-2), 60.4 (C-20), 57.5 (C-31), 56.9 (C-34), 51.6 (C-7), 49.9 (C-11), 47.4 (C-25), 47.0 (C-5), 45.7 (C-23), 40.4 (C-35), 36.1 (C-8), 35.4 (C-12, C-26), 30.4 (C-3), 29.5 (C-21), 25.1 (C-4), 24.7 (C-36), 24.3 (C-28), 22.9 (C-37), 21.4 (C-38), 20.9 (C-22), 15.1 (C-32), 14.9 (C-29), 10.9 (C-27)。以上数据与文献[10]基本一致,故将化合物2鉴定为hymenamide D。
化合物3:无色无定形粉末,茚三酮显色阴性。HRESIMS给出准分子离子峰:m/z 767.4468 [M+H]+ (calcd 767.4456),确定其分子量为766。结合1H和13C-NMR谱确定其分子式为C39H58N8O8,计算不饱和度为15。1D NMR谱图给出典型的肽类化合物特征信号。其中,1H NMR谱显示有5个低场区的酰胺氨基质子信号(δH 8.80, 8.13, 7.98, 7.95, 7.25),7个α-次甲基质子信号(δH 4.65, 4.28, 4.24, 4.19, 4.14, 3.89, 3.83)。13C NMR谱提示有7个酰胺羰基碳信号(δC 171.4, 171.1, 170.9, 170.3, 170.2, 170.1, 169.6),7个α-次甲基碳信号(δC 62.3, 61.5, 60.2, 57.1, 55.2, 51.0, 49.3)。据此推断该化合物可能为七肽。结合ESI-MS/MS质谱数据确定其氨基酸残基组成为两个脯氨酸残基、一个亮氨酸残基、一个苯丙氨酸残基、一个天冬酰胺残基和两个缬氨酸残基,残基连接顺序为cyclo-(Pro-Asn-Val-Pro-Leu-Val-Phe)。通过高级Marfey法确定所有氨基酸残基均为L构型。将核磁共振数据归属如下:1H NMR (600 MHz, DMSO-d6) δH 8.80 (1H, d, J = 5.4 Hz, 21-NH), 8.13 (1H, d, J = 9.5 Hz, 32-NH), 8.01 (1H, s, 9-NH2), 7.98 (1H, d, J = 8.5 Hz, 11-NH), 7.95 (1H, d, J = 6.1 Hz, 7-NH), 7.28 (1H, m, 9-NH2), 7.25 (3H, m, 27-NH, H-35, H-39), 7.18 (1H, d, J = 7.4 Hz, H-37), 7.14 (2H, d, J = 7.6 Hz, H-36, H-38 ), 4.65 (1H, m, H-7), 4.28 (1H, d, J = 7.7 Hz, H-32), 4.24 (1H, m, H-16), 4.19 (1H, m, H-21), 4.14 (1H, t, J = 8.6 Hz, H-27), 3.89 (1H, t, J = 8.6 Hz, H-2), 3.83 (1H, t, J = 7.9 Hz, H-11), 3.75 (1H, m, H-5a), 3.46 (2H, m, H-5b, H19a), 3.26 (1H, m, H19b), 3.06 (1H, m, H-8a), 2.94 (3H, m, H-8b, H33a, H33b), 2.34 (1H, m, H-17a), 2.19 (2H, m, H-3a, H12), 2.02 (1H, m, H-28), 1.96 (1H, m, H-18a), 1.85 (1H, m, H-4a), 1.71 (2H, m, H-18b, H-23), 1.61 (1H, m, H-22a), 1.46 (1H, m, H-4b), 1.23 (1H, m, H-17b), 1.19 (1H, m, H-22b), 0.99 (1H, m, H-3b), 0.92 (3H, d, J = 6.7 Hz, H-13), 0.89 (3H, d, J = 6.8 Hz, H-14), 0.86 (6H, d, J = 6.7 Hz, H-29, H-30), 0.84 (3H, d, J = 6.7 Hz, H-25), 0.79 (3H, d, J = 6.4 Hz, H-24); 13C NMR (150 MHz, DMSO-d6) δC 172.5 (C-9), 171.4 (C-26), 171.1 (C-20), 170.9 (C-31), 170.3 (C-1), 170.2 (C-15), 170.1 (C-10), 169.6 (C-6), 138.4 (C-34), 128.9 (C-35, C-39), 128.1 (C-36, C-38), 126.2 (C-37), 62.3 (C-2), 61.5 (C-11), 60.2 (C-16), 57.1 (C-27), 55.2 (C-32), 51.0 (C-21), 49.3 (C-7), 47.6 (C-5), 45.8 (C-19), 37.9 (C-22), 37.0 (C-33), 35.5 (C-8), 30.5 (C-17), 30.1 (C-28), 29.5 (C-12), 29.2 (C-3), 25.1 (C-4), 24.2 (C-23), 23.3 (C-24), 21.3 (C-18), 20.6 (C-25), 19.7 (C-13), 18.7 (C-14, C-29), 18.3 (C-30)。以上数据与文献[11]基本一致,故将化合物3鉴定为axinastatin 2。