J. Hattori Bot. Lab. No. 74: 121- 138 (Nov. 1993) CHEMICAL CONSTITUENTS OF 25 LIVERWORTS 1 1 TOSHIHIRO HASHIMOT0 , YOSHINORI ASAKAWA , KATSUYUK.l NAKASHIMA1 AND MOTOO Toru1 ABSTRACT. Twenty-five liverworts were investigated chemically and 20 new compounds isolated and their structures characterized by spectroscopic evidence, X-ray analysis and chemical correlation. The chemosystematics of each species is discussed. INTRODUCTION Liverworts are rich sources of terpenoids and lipophilic aromatic compounds; these are very valuable for chemosystematic investigation. Previously, we have reported the chemical constituents of 700 species of liverworts and discussed the chemosystematics at family and genus level (Asakawa l 982a, b; 1993, Asakawa & Inoue l 984a; l 987a). Here we report the isolation and distribution of the terpenoids and aromatic compounds of 25 liverworts and discuss the chemical markers of each species. EXPERJMENTALS The liverworts collected in Japan and other countries shown in Table 1, were purified and dried for 1 to 7 days and then ground mechanically and extracted with ether or methanol for 7 to 30 days. Each extract was filtered and the solvent evaporated to give green crude oils, followed by chromatography on silica gel or Sephadex LH-20, using n­ hexane-ethyl acetate (EtOAc) and methanol-chloroform (1 : 1), respectively. Each fraction was further purified by a combination of preparative TLC (n-hexane-EtOAc 4 : 1) and preparative HPLC (µ.porasil; n-hexane-EtOAc 2 : 1). The stereostructures were elucidated by the analysis of spectroscopic data (UV, IR, MS, NMR and CD) and X-ray analysis or chemical correlation. The stereostructures of each compound characterized by the above methods are shown in Chart 1 and the structural elucidation of the new compounds will be reported elsewhere. RESULTS AND DISCUSSION Asterella sp. (Grimaldiaceae). A small thalloid liverwort collected in Langkawi island, Malaysia was identified as Asterella species. The liverwort emits an extremely unpleasant smell when crushed. This smell betrays to the presence of 20% of skatol (1). This is the first detection of skatol in liverworts so far examined. The major component of the extract is 3,4-dimethoxystyrene (2). These two aromatic compounds are significant chemical markers of this unidentified Asterella species. Blasia pusilla (Blasiaceae). As reported earlier, four sterols, brassicasterol, campes­ terol, stigmasterol and sitosterol are widely distributed not only in liverworts but also in 1 Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima 770, Japan. 122 J. Hattori Bot. Lab. No. 74 I 9 9 3 Table I. Terpenoids and aromatic compounds from Hepaticae. Species Weight Collected site and date Compounds detected Asterella sp. 20g Langkawi island, Malaysia, Skatol (1), 3,4-Dimethoxystyrene (2) July 22, 1992, coll. Y. Asakawa, T. Hashimoto, and H. Tanaka Blasia pusilla 365g Sanagouchi-son, Riccardin C (3), Riccardin F (4), Tokushima, Japan, Sep. 22, Orsellinic acid methyl ester (5) 1991, coll. T. Hashimoto Cheilolejeunea 20g Langkawi island, Malaysia, Serpentiphenol (6), serpentina July 24, 1992, coll. Serpentianic acid (7) Y. Asakawa, T. Hashimoto and H. Tanaka Cheilolejeunea 19g Langkawi island, Malaysia, Trifarienol A (8), Trifarienol B (9), trifaria July 24, 1992, coll. Trifarienol C (10), Trifarienol D (11), Y Asakawa, T. Hashimoto Trifarienol E (12) and H. Tanaka Conocephalum 1870g Saarbriicken, Germany, a-Tepinenol (13), Epi-cubenol (14), conicum July 7, 1988, coll. 22-Hydroxyhopane (15), Y. Asakawa 2-Acetoxygermacra-l ( 10),4( 14 )-dien- 6-one (16), Germacra-1(10)£,5£-dien- 4,8-ol (17) Conocephalum 236g Saarbriicken, Germany, Epi-cubenol (14), Germacra-1(10)£,5£- conicum August, 1991, coll. dien-4,8-ol (17), conocephalenol (18), Y. Asakawa ( + )-Cubebol ( 19), (- )-Selin- I I-en- 4a-ol (20) Frullania 192g Arisan, Taiwan, May 8, Nepalensolide A (21), Nepalensolide B nepalensis 1985, coll. Y. Asakawa (22), Nepalensolide C (23), Nepalensolide D (24), Tamariscol (25), 3,3'-Dimethoxy-4,5- methylenedioxybibenzyl (26) Frullania 9lg Kisawa-son, Tokushima, 11a,13-Dihydro-,8-cyclocostunolide (27), tamarisci Japan, Nov. 23, 1991, coll. 4-Epi-arbusculin A (28), Eudesmanal subsp. T. Hashimoto (29), ( + )-5a,7,8(H)-Eudesm-4a,6a-diol obscura (30), Methoxyfrullanolide (31) Frullania 1 49g Venezuela, Apr. 23, a-Cyclocostunolide (32), 3-Methoxy- 1991, coll. M. Tori 3',4'-methylenedioxybibenzyl (33), Rothin A acetate (34), Methyl 3a- hydroxy-l 8-oleanen-28-oate (35) Frullania 2 49g Venezuela, Apr. 23, ( + )-Cyclocolorenone (36), 1991, coll. M. Tori Hurnulenol acetate (37) T. HASHIMaro et al. : Chemical constituents of 25 liverworts 123 Table 1. (Continued) Species Weight Collected site and date Compounds detected Heteroscyphus 567g Bizan, Tokushima, Japan, 13-Epi-neoverrucosan-5/3-ol (38), pianus Dec. 20, 1990, coll. 13-Epi-neoverrucosane-5/3, 20-diol (39), T. Hashimoto, I. Nakamura, Heteroscyphone A ( 40), Heteroscyphone T. Nakayama, M. Horie, B (41), Heteroscyphone C (42), and A. Yasuda Heteroscyphone D ( 43), Heteroscyphol (44), Plagiochiline C (45), Plagiochiline L ( 46), Plagiochiline M ( 47), ( + )-7-Hydroxycalamenene ( 48), ( + )-5, 8-Dihydroxycalamenene ( 49) Lunularia 62g Tokushima-city, Tokushima, Perrottetin F (50), cruciata Japan, Dec. 8, coll . 7',8'-Dehydroperrottetin F (51), T. Hashimoto, A. Yasuda, 7',8'-Dehydroperrottetin F dimer (52) and Y. Yamaoka Marchantia 199g Ecuador, 1988, coll. Lunularin (53), Marchantin C (54) chenopoda S. R. Gradstein, R. Mues and J.-P. Frahm Marchantia 6670g Icyu-son, Tokushima, Marchantin C (54), Marchantin A (55), paleacea Japan, Nov. 25 , 1991, Marchantin B (56), Marchantin D (57), var. diptera coll. T. Hashimoto Marchantin E (58), Paleatin A (59), Paleatin B (60) Marchantia 360g Oohara-cho, Okayama, Marchantin C (54), Marchantin A (55), polymorpha Japan, Aug. I, 1991, coll. Marchantin B (56), Isoriccardin C (61) T. Hashimoto, T. Nagai and A. Yasuda Omphalanthus 54g Colombia, July, 1991 , ( + )-/3-Chamigrene (63), (+)-Methyl filiformis coll. S. R. Gradstein chamigrenate (64), Methyl omphalate (65), 5-Heptadeca-8(Z),1 l(Z),14(Z)- trienylresorcinol monomethyl ether (66) Pallavicinia 146g Sanagouchi-son, Japan, Sacculatal (67), Pallavicinol (68) levieri Oct. 10, 1990, coll. T. Hashimoto Pellia 570g Icyu-son, Tokushima, Perrottetin E (69), Perrottetin E endiviifolia Japan, Apr. 29, 1987, I !'-methyl ether (70), 14-Hydroxy- (female) coll. T. Hashimoto perrottetin E 11 '-methyl ether (71) Pellia 10170 g Nakamura-city, Kouchi, Sacculatal (67), Isosacculatal (72) endiviifolia Japan, Jan. 2, 1987. coll. 1/3-Hydroxyisosacculatal (73), (male) T. Hashimoto Sacculatanolide (74), 1/3-Hydroxy- sacculatanolide (75), 1/3,11 a- Dihydroxysacculatanolide (76), I /3, 11 a -Dihyroxysacculatenolide (77), 12-Deoxo-1/3,l la-dihyroxy- sacculatanolide (78) 124 J. Hattori Bot. Lab. No. 74 l 9 9 3 Table 1. (Continued) Species Weight Collected site and date Compounds detected Plagiochila 27g Venezuela, Apr. 23, Fusicogigantone A (79), Spathulenol, corrugata 1991, coll. M. Tori (80), 8-epi-sclareol (81), PC-1 (82) Plagiochila 1086g Todoroki-Falls, Plagiochiline C (45), Plagiochilide (83), fruticosa Kainan-cho, Tokushima, Plagiochiline A (84), 3a,l l-Diacetoxy- Japan, March 8, 1992, coll. 2a-hydroxybicyclogermacrene (85), T. Hashimoto lsoplagiochin A (86), lsoplagiochin B (87) Plagiochila l 170g Kajigamori, Kouchi, Spathulenol (80), Bicyclogermacrene ovalifolia Japan, May 4, 1985, coll. (88), Maalian-5-ol (89), Plagiochiline Y. Asakawa, and N (90) T. Hashimoto Pore/la 466g Marys Pk., Oregon, U.S.A, Polygodial (91), Cinnamolide (92), roellii Feb. 6, 1984, coll. Confertifoline (93), lsodrimenol (94), T. Hashimoto 6a-Hydroxyisodrimenol (95), 6,7- Dehydroisodrimenin (96), Aristolone (97), Dehydroabietic acid (98) Porella 120g Hiwasa-cho,Tokushima, Caespitenone (99), Santalene-type subobtusa Japan, Dec. 31 , 1991 , coll. alcohol (100) T. Hashimoto Porella 300g Colombia, May 28, 1991, Caespitenone (99), Swartzianin A (101), swartziana coll. S. R. Gradstein Swartzianin B (102), Swartzianin C (103), Swartzianin D (104), Seco- swartzianin A (105), Secoswartzianin B (106), Germacra-4-en-1 ,6-dione (107), Guai-3-en-1-ol-6-one (108), Guai-4(14)-en-1-ol-6-one (109) Ptychanthus 283 g Kisawa-son, Ptychanthin A (110), Ptychanthin striatus Tokushima, Japan, B (111), Ptychanthin C (112), Nov. 23, 1991 , coll. Ptychanthin D (113), Ptychanthin T. Hashimoto E (114), Ptychanthin F (115), Ptychanthin G (116), Ptychanthin H (117), Deoxypinguisone (118), Pinguisanene (119), Ptychanolide, (120), Ptychanolactone (121) Reboulia 1127 g Kisawa-son, Riccardin C (3), Marchaotin C (54), hemisphaerica Tokushima, Japan Marchantin C 13-methyl ether (122), Apr. 29, 1992, coll. 6,11 ,22-Hopanetriol (123), RH-I T. Hashimoto (124), RH-2 (125) T. HASHIMOTO et al. : Chemical constituents of25 liverworts 125 higher plants. These have been found in B. pusilla (Asakawa 1982a). Further fractionation of the methanol extract resulted in the isolation of two macrocyclic aromatic compounds, riccardin C (3) and riccardin F (4), along with orsellinic acid methyl ester (5). B. pusilla is chemically very close to Riccardia multifida (Riccardiaceae) because both species produce the same macrocyclic compounds (3) as the major component (Asakawa 1982a; 1993, Asakawa et al. 1983). Cheilo/ejeunea serpentina (Lejeuneaceae). Two new sesquiterpenoids, serpentiphenol (6) and serpentianic acid (7) have been isolated from C. serpentina. The latter compound belongs