将258 mg焦脱镁叶绿酸-a甲酯(1b, 0.470 mmol)溶解于20 mL二氯甲烷中, 搅拌下加入106 mg钯碳, 室温条件下通入氢气, 当反应体系的紫外可见光谱中在668 nm处的吸收峰消失后停止反应, 过滤, 用二氯甲烷洗涤, 合并滤液和洗涤液, 用无水硫酸钠干燥, 减压除尽溶剂.将所得固体混合物溶解于10 mL冰乙酸中, 搅拌下再加入6 mL浓磷酸和7 mL浓盐酸, 搅拌3 min后再慢慢滴加10 mL 40%的甲醛水溶液, 35 ℃下搅拌反应24 h.先后向反应体系加入40 mL水和40 mL二氯甲烷, 分出有机层, 水层用二氯甲烷萃取(30 mL×3), 合并有机层并水洗至中性, 用无水硫酸钠干燥, 除去95%的溶剂后用重氮甲烷甲基化, 减压浓缩, 剩余物经硅胶柱层析分离[洗脱剂: V(石油醚):V(乙酸乙酯)＝2:1], 得到112 mg红色固体7 (0.193 mmol).产率41%. m.p. 213~215 ℃; UV-vis (CH₂Cl₂)λ_max [ε/(L•mol^－1•cm^－1)]: 412 (1.12×10⁵), 510 (8.56×10³), 544 (2.67×10⁴), 609 (3.74× 10⁴), 666 (6.34×10⁴) nm; ¹H NMR (CDCl₃) δ: －1.34 (br s, 1H, NH), 0.70 (br s, 1H, NH), 1.50 (d, J＝7.0 Hz, 3H, 18-CH₃), 1.68 (t, J＝7.6 Hz, 3H, 3a-CH₃), 1.71 (t, J＝7.6 Hz, 3H, 8a-CH₃), 2.11~2.23 (m, 2H, 17a+17bH), 2.32~2.52 (m, 2H, 17a+17b-H), 3.66 (q, J＝7.6 Hz, 2H, 8a-H), 3.84~3.92 (m, 2H, 3a-H), 3.27, 3.45, 3.54, 3.63 (each s, each 3H, CH₃+OCH₃), 4.20 (dd, J＝8.2, 3.3 Hz, 1H, 17-H), 4.80 (q, J＝7.2 Hz, 1H, 18-H), 5.13 (d, J＝19.8 Hz, 1H, 13²-H), 5.19 (d, J＝19.8 Hz, 1H, 13²-H), 6.01 (d, J＝12.8, 1H, 20-CH₂), 6.36 (d, J＝12.8, 1H, 20-CH₂), 9.32, 9.43 (each s, each 1H, meso-H); IR (KBr) v: 3469 (N—H), 2929 (C—H), 1747, 1699 (C＝O), 1606 (C＝C), 1534 (chlorin skeleton), 1457, 1311, 1171, 1143, 1020 cm^－1; EI-MS m/z: 581.2 (M+H⁺). Anal. calcd for C₃₅H₄₀-N₄O₄: C 72.39, H 6.94, N 9.65; found C 72.19, H 7.06, N 9.77.