Agric. Biol. Chem., 55 (7), 1787-1792, 1991 1787

Ideamine A^Oxides: Pyrrolizidine Alkaloids Sequestered by the Danaine , leuconoe Ritsuo Nishida, Chul-Sa Kim, Hiroshi Fukami and Ryozo Irie* Pesticide Research Institute, Faculty of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606, Japan . * Department of Agricultural Chemistry, Shinshu University, Kamiina-gun, Nagano 399-45, Japan Received January 8, 1991

Twonew pyrrolizidine alkaloids, ideamines A and B, together with other analogs (lycopsamine and parsonsine) were isolated in the TV-oxide forms from adult bodies of the Apocynaceae-feeding danaine butterfly, Idea leuconoe. Ideamine A was characterized as a homolog of lycopsamine, in which the viridifloric acid moiety was replaced by a 2-ethyl-2,3-dihydroxybutanoic moiety. Likewise, ideamine Bwas identified as a nor-derivative of parsonsine, in whichthe trachelanthic acid moiety was replaced by a 2-ethyl-2,3-dihydroxybutanoic moiety diastereomeric to the necic acid from ideamine A.

Idea leuconoe Erichson is a large danaine Four alkaloid components (1-4) were butterfly whose larvae feed exclusively on the isolated from an extract of laboratory-reared plant, laevigata Alston (Apocyna- /. leuconoe adults by reverse-phase liquid ceae), in the Ryukyu Islands of Japan. Wehave chromatography.1} The molecular weights of isolated four pyrrolizidine alkaloids, both from compounds 1^1 were determined to be 301, the (adult bodies and eggs) and from the 315, 441 and 455, respectively, from the host plant, demonstrating the acquisition of secondary ion mass spectra (SIMS). the alkaloids directly from the larval host in Compound2 was identified as lycopsamine this species.1} These alkaloids were found TV-oxide, since 2 yielded lycopsamine (2a, predominantly as TV-oxides in the insect tissues C15H25NO5, [a]D +4.2°; lit. [a]D +3.3°,2> as well as in the plants. We report here the [a]D +4.8o3)) when treated with zinc dust in identification of the alkaloid components, diluted sulfuric acid. The identity of 2a was which were isolated from the bodies of /. confirmed from its diagnostic 1H- and leuconoe, including two new analogs, ideamine 13C-NMRspectra,3) and by alkaline hydrolysis A and B JV-oxides. of 2a to (-)-viridifloric acid (5) and (+)- 1788 R. Nishida et al. retronecine (6). dihydroxybutanoic acid. The 1H-NMR spec- Compound4 was identified as parsonsine trum of la exhibited AB-type doublet signals TV-oxide, since the ^-NMR signals of its by C-9 methylene protons at £4.75 and 4.87 Zn-reduced product 4a (C22H33NO8, [a]D (.7= 13Hz), indicating the acyl moiety to be +15°) coincided with those reported for attached to the C-9 position.3) Thus, the parsonsine (lit. [a]D + 19.8°).4) Further confir- structure of ideamine ATV-oxide was given as mation was provided by alkaline hydrolysis that shown in formula 1. The 1H- and of the macrocyclic ester 4a to ( + )-retronecine 13C-NMRassignments of 1 are listed in Tables (6), trachelanthic acid (7) and a-isopropylmalic I and II in comparison with 2, which were given acid (8). with the help of two-dimensional NMR Compound 1 was reduced to free alkaloid analyses (H-H COSY and C-H COSY la ([a]D +4.0°), the molecular formula of spectra). which was determined to be C14H23NO5. Compound 3 yielded free alkaloid 3a Compound la gave (+)-retronecine (6) and (C21H31NO8, [a]D +21°) by Zn reduction. esterifying acid 9 ([a]D -5.9°). The ^-NMR Upon alkaline hydrolysis, 3a gave (+)-6 and spectrum of9 exhibited a methyl triplet (3 0.86) two necic acids (8 and 10). Dioic acid 8 showed coupled to a methylene quartet at 51.79 a negative optical rotation ([a]D -17°), and (/=7.4Hz), and a methyl doublet ((51.15) thereby C-2" should possess an S-configura- coupled to a methine quartet at 53.93 tion.5) The XH- and 13C-NMR and mass (/=6.6Hz). Combined with 13C-NMR and spectra for 10 gave very similar patterns to mass spectrometric data (see the experimental those for 9. The ^-NMRspectrum of 10, section), 9 was identified as 2-ethyl-2,3- however, gave a methyl triplet (S O.S3) coupled Table I. ^-NMRSpectral Assignments of Compounds 1, 2, 3 and 4 (Chemical Shifts, Multiplicity and /-Values in Hz) Compound1 Compound2 Compound3 Compound4 2 5.86br.s 5.87br.s 5.96 br.s 6.03 br.s 3a 4.50d (16) 4.48d (16) 4.68d (16) 4.66d (16) 3b 4.40d (16) 4.39 (16) 4.45 (16) 4.45 (16) 5a 4.24dd (8.7, ll.5) 4.17dd (8.3, ll.5) 3.7-3.8m 3.7-3.8 m 5b 3.76dt (5.5, ll.5) 3.78dt (5.9, ll.5) 6a 2.61m 2.61m 3.19m 3.04m 6b 2.07m 2.06m 2.16dd (5.5, 13.6) 2.17dd (5.9, ll.5) 7 4.68 br.s 4.67br.s 5.98m 5.94br.t (3) 4.68 br.s 4.67 br.s 5.24m 5.01m 4.90d (13.5) 4.90d (14.5) 4.90d (14) 4.96d (13.5) 4.76d (13.5) 4.76d (14.5) 4.84d (14) 4.76d (13.5)

3' 3.83q (6.5) 3.96q (6.6) 5.23q (6.4) 5.43q (6.3) 4' 1.21d (6.5) 1.27d (6.6) 1.24d (6.4) 1.25d (6.3) 5'a 1.85dq (14.4, 7.2) 2.18 septet (6.7) 1.5-1.8m 1.89 septet (7) 5'b 1.72dq (14.4, 7.2) 6'a 0.91 1 (7.2) 0.94d (6.7) 0.891 (7.4) 1.01 d (7) 6'b 0.88d (6.7) 0.96d (7)

3"a 2.87d (16.5) 2.87d (16.5) 3"b 2.60d (16.5) 2.58d (16.5) 5" 1.69 septet (6.7) 1.71 septet (6.7) 6"a 0.97d (6.7) 0.97d (6.7) 6"b 0.83d (6.7) 0.83d (6.7)

Compounds 1 and 2weremeasuredin CDC13+CD3OD(9 : 1), andcompounds 3 and4weremeasured in CDC13. Ideamine TV-Oxides from Danaine Butterfly 1789

Table II. 13C-NMRSpectral Assignments of Compounds 1, 2, 3 and 4 Compound1 Compound2 Compound3 Compound4 1 132.26 132.31 130.14 130.01 2 122.80 122.95 125.31 126.97 3 78.02 78.12 80.50 80.34 5 69.10 69.17 70.28 70.38 6 34.55 34.55 32.78 32.91 7 69.71 69.70 75.47 75.78 8 95.79 95.89 95.67 96.29 9 61.49 61.51 60.39 60.53 r 173.80 173.91 173.22 172.49 2' 81.81 84.20 79.90 82.12 3' 72.71 71.81 76.36 74.95 4' 17.45 17.06 13.22 12.98 5' 28.36 32.36 28.85 33.96 6'a 7.83 15.68 8.06 17.23 6'b 17.80 17.31 1" 174.63 175.07 2" 76.14 76.35 3" 43.08 42.79 4" 168.ll 167.57 5" 36.57 36.21 6"a 16.12 16.17 6"b 17.21 17.14

Compounds 1 and 2weremeasuredin CDC13+ CD3OD(9 : 1), andcompounds 3 and4weremeasuredin CDC13. to a methylene multiplet at around 51.6 as the pyrrolizidine alkaloid components (/-7.4Hz), and a methyl doublet (51.15) incorporated by /. leuconoe. Ideamine TV-oxides coupled to a methine quartet at 53.98 (1 and 3) were the homologs of 2 and 4, (/=6.5Hz). These data indicate that com- respectively, lacking one carbon unit from the pound 10 was a diastereoisomer of 9. The hydroxybutanoic moiety. It should be noted 2D-NMR analyses (H-H COSY and C-H that the necic acids (9 and 5) contained in COSY) of compound 3 exhibited parallel monoesters 1 and 2 were diastereomeric to the correlations to those found for compound4, corresponding necic acids (10 and 7) in- except for the C-2' alkyl portions, suggesting corporated in cyclic esters 3 and 4, respectively, the same14-memberedmacrocyclic structure although the absolute configuration at C-2' and for 3. Conclusive evidence for the arrangement C-3' of the ideamines remains to be clarified. of the ester linkages was obtained by the Several analogs of parsonsine have been COLOC (correlation spectroscopy via long- reported from two species of Parsonsia (P. range coupling) spectrum of 3, in which heterophylla and P. spiralis).^ Although a correlation was observed between H-7 (5 5.98) number of macrocyclic pyrrolizidine esters are and C-l" (5 174.63), and between H-9ab (54.84 known from various plants in the family and 4.90) and C-l' (5173.22). Further, a Compositae and Leguminoseae, the 14-mem- significant NOE correlation was observed bered ring system seems to be characteristic of between the H-3' methine (55.23) and H-3" the genus Parsonsia.6) A monoester, parsonine methylene (52.60 and 2.87) in the NOESY (the 5,6-dihydro-7-oxopyrrolizine derivative of spectrum. Thus, the structure of ideamine B (-)-viridifloric ester), which is analogous to TV-oxide was given as that shown in formula 3. 2a, has been isolated from stems of P. Twomonoesters (1 and 2) and two cyclic laevigata. 1) triesters (3 and 4) have been characterized here Lycopsamine (2a) has been found in the 1790 R. Nishida et al. adult bodies of various danaine represent (broad) singlet, (double) doublet, triplet, quartet together with other types of pyrrolizidine and multiplet, respectively, and coupling constants are given in Hz. 13C-NMRassignments with asterisks may be esters.8) Compoundla (or its stereoisomer) has interchanged. also been tentatively identified from extracts of Solomon Island danaines (Euploea nomertes Isolation of N-oxides 1-4. Larvae of Idea leuconoe were polymela and Danaus juventa).9) In most of raised on leaves of P. laevigata. Thirty adults immediately these cases, the alkaloids seem to have been after emergence were soaked and ground in ethanol incorporated during the adult stage by foraging (200 ml) and extracted with a mixture of ethanol, acetone from the pyrrolizidine-containing plants.10) and chloroform (1:1:1, 100mlx3). Filtration of the combined extract (Toyo filter paper, qualitative no. 2) and Males of/. leuconoe did not seem to show such evaporation of the solvent under reduced pressure gave an affinity to the plants, probably because they oily residue (1.7g), which was dissolved in water (120ml) did not need to ingest additional quantities of and washed with chloroform (100ml x 2). The aqueous the alkaloids.11} Acquisition of the alkaloids layer (0.4g) was subjected to chromatography in a reverse-phase open column (25g of ODS-W,microbead by the larva from the host plant has been also silica gel 5D, 100-200 mesh, Fuji-Davison Chemical Ltd.), shownin an adult of E. treitschkei aenea raised eluting in sequence with 100ml of water (fraction 1), 10% on P. spiralis,9) and in the primitive Ithomiinae, methanol in water (fraction 2), 20% methanol in water Tithorea harmonia pseudethra, which feed on (fraction 3), 30% methanol in water (fraction 4), 40% Prestonia acutifolia (Apocynaceae).12) In the methanol in water (fraction 5), 50% methanol in water case of /. leuconoe, individual adults se- (fraction 6), and 70% methanol in water (fraction 7). Compounds1 and 2 were isolated in almost pure states questered over 3mg of total TV-oxides in the from fractions 3 and 4, respectively. Fractions 5 and 6 body tissues. It is noteworthy that both sexes were rich in 3 and 4, respectively. Compounds 3 and 4 sequester the alkaloids from the larval host in were purified by preparative HPLC (/zBondasphere 5/i C18, these species, while the acquisition in those 100A, 150mm x 19mm i.d.), eluting with 25% acetonitrile (5ml/min). Compounds 3 and 4 were isolated at tR= l2.0 pharmacophagous species was primarily male- biased.10) Females of /. leuconoe could thus and 17.9min, respectively. The yield of each compound from 30 butterflies was as follows: 1, 27mg; 2, 39mg; 3, equally obtain the defense measure and 30mg; and 4, 5mg. consequently transfer portions of the alkaloids Compound 1 (ideamine A TV-oxide), [a]3/ + 5.0° (c=2.0, to eggs.1} /. leuconoe seems to have obtained MeOH). SIMS m/z: 302 (M++l). EIMS m/z (%): 285 (M+-16, 5.7), 241 (4), 154(14), 139 (53), 138 (100), 123 such an ecological advantage by feeding solely (36), 122(27), 94(35), 93 (44),43 (14). *H- and 13C-NMR: upon P. laevigata, which might preserve the listed in Tables I and II. original feature of an ancestral foodplant of Compound 2 (lycopsamine TV-oxide), [a]3)2 +6.0° (c=2.3, MeOH). SIMSm/z: 316(M+ + 1). EIMSm/z(%): the .13) 299 (M+-16, 8), 279 (8), 255 (6), 156 (16), 151 (35), 140 (28), 139 (81), 138 (100), 137 (59), 136 (87), 123 (20), 120 Experimental (33), 119 (52), 118 (78), 117 (53), 103 (57), 94 (65), 93.(60), 43 (38). 1U- and 13C-NMR: listed in Tables I and II. Instruments. SIMS and electron impact mass spectra Compound 3 (ideamine B TV-oxide), [a]3/ +24° (c- 3.7, (EIMS) were recorded with a Hitachi M-80 mass MeOH). SIMS m/z: 442 (M++l). EIMS m/z (%): 441 spectrometer. SIMSwas measured at 8 kV with Xe as the (M+, 0.05), 425 (5.4), 397 (2), 382 (2), 381 (4), 296 (35), primary beam gas, the samples being applied to a silver 234 (21), 135 (8), 117 (100), 90 (22), 43 (5). XH- and sample stage mixed with glycerol. EIMS of the free 13C-NMR: listed in Tables I and II. alkaloids (la-4a) in the high-resolution mode were Compound4 (parsonsine TV-oxide), [a]3/ +21° (c=0.75, measured at 70 eV (in-beam), and otherwise measured at MeOH). SIMS m/z: 456 (M++l). EIMS m/z (%): 439 20 eV. Optical rotation was measured with a Jasco DIP-4 (M+-16, 3.2), 411 (2), 395 (7), 324 (6), 296 (49), 229 (6), digital polarimeter. *H- and 13C-NMR spectra of the 138 (ll), 131 (44), 120 (81), 119 (100), 118 (56), 117 (61), TV-oxides (1-4), including the two-dimensional correlation 113 (22), 90 (20), 71 (31), 43 (22). XH- and 13C-NMR: spectra, were measured with a Brucker AC-250 (250 MHz) listed in Tables I and II. instrument, and those of others were measuredwith a JEOL JNM FX-90Q spectrometer (90MHz). DSS (in Reduction ofN-oxides (1-4). Compound 1 (24mg) was D2O)or TMS(in the other solvent system) was used as dissolved in 2n H2SO4(1.5ml), stirred for 3hr with zinc the internal standard. Letters (br.)s, (d)d, t, q and m dust (66 mg) at 10°C and then filtered. The solution, after Ideamine TV-Oxides from Danaine Butterfly 1791 being made alkaline to pH 12 with ammonia, was passed 7= 18, 10), 2.2-2.0 (2H, m), appox. 1.85 (2H, m), 1.27 (3H, through a Sep-pak C18 cartridge (Waters Associates), d, 7=6.4), 1.04 (3H, d, J=6.6), 0.98 (6H, d, 7=7), 0.84 eluting with an additional 3ml of water and then with (3H, d, 7=6.6). 13C-NMR (CDC13+CD3OD, 10: 1) 3: 67% MeOHin water (3ml). Product la was recovered 176.23 (C-l"), 172.33 (C-l'), 167.45 (C-4"), 132.29 (C-l), from the latter eluate (15.6mg yield). Compound 2 was 130.24 (C-2), 82.29 (C-21), 77.20 (C-8*), 76.55 (C-7*), 74.81 readily reduced in the same manner to 2a, whereas lOhr (C-3'*), 63.28 (C-9**), 60.89 (C-3**), 52.60 (C-5), 42.42 were necessary to complete the reduction of macrocyclic (C-3"), 35.59 (C-5"), 34.83 (C-6), 33.53 (C-5'), 16.96 (C-6', compounds 3 and 4 to free alkaloids 3a and 4a (at 30°C). C-6"), 16.79 (C-6"), 16.04 (C-6'), 12.68 (C-4'), (the signal Compound la (ideamine A), [a]3/ +4.0° (c=\.25, for C-2" was not observed due to its low intensity). EtOH). EIMS m/z (%): 285.1576 (calcd. for C14H23NO5: 285.1575; M+, 8), 241 (6), 156 (14), 140 (28), 138 (100), Hydrolysis of la. Ideamine A (la, 13.5mg) was mixed 120 (21), 94 (72), 93 (64), 80 (14), 43 (8). ^-NMR with 18mg of Ba(OH)2-8H2O and 0.5ml of water, and (CDCI3+CD3OD, 10: 1) <5: 5.85 (1H, brs), 4.87 (1H, d, held at 95°C for 2hr. The solution was saturated with /=13), 4.75 (1H, d, 7=13), 4.4-4.0 (2H, m), 3.83 (1H, q, CO2, the precipitated BaCO3 being removed by nitration 7=6.5), 3.9-3.2 (3H,m), 2.75 (1H, dd, 7=18, 10), 2.1-1.8 and was then passed through a short column of Dowex (2H, m), 1.82 (2H, q, 7=7.3), 1.19 (3H, d, J=6.5), 0.89 50Wx 8 (200-400 mesh, 40mmx 3.5 mmi.d.), eluting with (3H, t, 7=7.3). 13C-NMR (CDC13+CD3OD, 10:1) S: 8 ml of water (acidic fraction) and with 8 ml of2N NH4OH 174.39(C-l'), 133.00(C-l), 128.77(C-2), 81.21 (C-2'), 77.90 (basic fraction). Compound 9 (6.3 mg yield) was recovered (C-8), 71.94 (C-3'), 70.70 (C-7), 62.41 (C-3*), 62.14 (C-9*), 53.63 (C-5), 35.92 (C-6), 28.33 (C-5'), 17.44 (C-4'), 7.64 from the acidic fraction, and retronecine (6, 7mg yield) wasobtained from the basic fraction as a crystalline solid. (C-6'). Compound 6 (retronecine). [a]£7 + 36° (c=0.58, EtOH). Compound 2a (lycopsamine). [a]^1 +4.2° (c=1.2, EIMS m/z (%): 155 (M+, 26), 111 (60), 94 (27), 93 (18), EtOH). EIMS m/z (%): 299.1715 (calcd. for C15H25NO5: 80 (100), 68 (16), 41 (9). ^-NMR (CDC13+CD3OD, 299.1730; M+, 1.6), 255 (2), 156 (6), 138 (100), 120 (6), 94 10: 1) 5: 5.72 (lH, br.s),4.4-4.1 (4H,m), 3.91 (1H, br.d, (28), 93 (37), 43 (5). ^-NMR (CDC13) S: 5.91 (1H, br.s), 7=16), 3.45 (1H,m), 3.23 (1H, m), 2.72(1H,m), 1.96 (2H, 4.82 (2H, m), 4.5-4.0 (2H, m), 3.97 (1H, q, 7=6.5), 3.88 m). 13C-NMR (CDC13+CD3OD, 10: 1) 3: 137.55 (C-l), (1H, m), 3.6-3.0 (3H, m), 2.73 (1H, dd, 7=18, 10), 2.17 126.61 (C-2), 79.15 (C-8), 70.91 (C-7), 61.76 (C-9*), 58.62 (2H, septet, 7=6.8), 1.95 (2H, m), 1.27 (3H, d, 7=6.5), (C-3*), 53.96 (C-5), 35.21 (C-6). 0.93 (3H, d, 7=6.8), 0.89 (3H, d, 7=6.8). 13C-NMR Compound 9 (2-ethyl-2,3-dihydroxybutanoic acid). (CDCI3) S: 174.39 (C-l'), 132.94 (C-l), 129.96 (C-2), 83.70 [a]js7 -5.9° (c=0.5, H2O). EIMS m/z (%): 104 (C-2'), 78.39 (C-8), 71.08 (C-3'), 71.08 (C-7), 62.90 (C-3*), (M+-C2H4, 100), 89 (92), 86 (19), 71 (28), 58 (28), 57 62.52 (C-9*), 53.85 (C-5), 36.24 (C-6), 32.45 (C-5'), 17.77 (51), 45 (29), 44 (15), 43 (54), 41 (22). ^-NMR (D2O) 5: (C-6'), 17.34 (C-6'), 15.98 (C-4'). 3.93 (1H, q, 7=6.6), 1.79 (2H, q, 7=7.4), 1.15 (3H, d, Compound3a(ideamine B). [a]3)1 +21° (c= 1.0, EtOH). 7=6.6), 0.86 (3H, t, 7=7.4). 13C-NMR (D2O) S: 179.86 EIMS m/z (%): 425.2059 (calcd. for C21H31NO8: 425.2048; (C-l), 83.97 (C-2), 73.84 (C-3), 30.72 (C-5), 19.12 (C-4), M+, 10), 397 (5), 381 (14), 324 (9), 296 (100), 138 (20), 9.70 (C-6). 136 (ll), 121 (51), 120 (74), 119 (37), 94 (13), 93 (24), 43 (2). ^-NMR (CDC13) 5: 5.89 (1H, br.s), 5.56 (1H, m), Hydrolysis of'2a. Lycopsamine (2a, 9 mg) was hydrolyzed 5.21 (1H, d, 7=13), 5.10 (1H, q, 7=6.4), 4.5-4.2 (2H, m), with barium hydroxide and treated in the same manner as 3.99(lH,br.d,/= 16),3.7-3.2(2H,m),2.84(lH,d,/= 16), that for la. Compounds 5 (4.3mg yield) and 6 (4.6mg 2.65 (1H, d, 7=16), 2.61 (1H, dd, 7=18, 10), 2.3-2.0 (2H, yield; [a]3}1 +42° (c=0.33, EtOH) were recovered from m), approx. 1.8(1H,m), 1.62(2H,m), 1.27(3H,d,7=6.4), the acidic and basic fractions, respectively. 0.96 (3H, d, 7=7), 0.92 (3H, t, 7=7), 0.85 (3H, d, 7=7). Compound 5 (viridifloric acid), [a]3/ -3° (c=0.5, H2O). 13C-NMR (CDC13) (5: 176.77 (C-l"), 173.20 (C-l'), EIMSm/z(%): 118 (M+-C2H4O, 59), 103 (100), 85 (34), 167.24 (C-4"), 132.40 (C-l), 129.64 (C-2), 80.83 (C-2'), 73 (12), 71 (ll), 57(32), 56(34),45 (17),43 (38). ^-NMR 77.52 (C-8*), 76.66 (C-3'*), 76.66 (C-2"), 76.01 (C-7*), (D2O) 3: 4.05 (1H, q, 7=6.5), 2.18 (1H, q, 7=6.9), 1.20 63.55 (C-3**), 61.92 (C-9**), 52.93 (C-5), 42.69 (C-3"), (3H, d, 7=6.5), 0.92 (3H, d, 7=6.9), 0.85 (3H, d, 7=6.9). 35.70 (C-5"), 35.00 (C-6), 27.74 (C-5'), 16.96 (C-6"), 16.25 13C-NMR (D2O) 3: 176.88 (C-l), 83.43 (C-2), 71.35 (C-3), (C-6"), 13.00 (C-4'), 7.91 (C-6'). 32.02 (C-5), 17.55 (C-4), 16.96 (C-6), 15.87 (C-6). Compound 4a (parsonsine). [a]£7 + 15° (c=0.4, EtOH). EIMS m/z (%): 439.2190 (calcd. for C22H33NO8: 439.2203; Hydrolysis 3a. Ideamine B (3a, ll mg) and Ba(OH)2à" M+, 8), 411 (5), 395 (10), 324 (15), 297 (41), 296 (100), 8H2O (40mg) were dissolved in 1 ml of water and held at 138 (25), 121 (65), 120 (94), 119 (49), 95 (15), 94 (ll), 93 95°C for 2hr. After being treated with CO2 gas, the (24), 43 (8). XH-NMR (CDC13): S: 5.92 (1H, br.s), 5.55 supernatant was separated into the acidic and basic (1H, m), 5.34 (1H, q, 7=6.4), 5.21 (1H, d, 7=13), 4.42 fractions with cation-exchange resin. Retronecine (6, Md7 (1H,m),4.32(1H,m), 3.98 (1H, br.d,J=15), 3.5-3.2(2H, + 37°, c = 0.3, EtOH) was recovered from the basic fraction m), 2.85 (1H, d,7=16), 2.66 (1H, d,7=16), 2.62 (1H, dd, (3.4 mg yield). The acidic fraction (7 mg) was separated by 1792 R. Nishida et al.

HPLC (Chemcopack Nucleosil 5C18, 300mmx 7.8mm Acknowledgment. Wethank Messrs. F. Kimura and i.d.; 15% methanoland 1%aceticacid inwater2.5 ml/min), Y. Nakatani of Kashihara City Insectarium for the insect and acids 10 and 8 were isolated at tR= 10.1 and 19.7min, supply. respectively (acid 9 was eluted at tR=7.4min under the same conditions). Addedinproof. Professor T. Yamauchi and Dr. F. Abe Compound 8 (a-isopropylmalic acid), [a]^6 -17° of Fukuoka University informed us that ideamine B (3a) (c=1.5, MeOH). EIMS m/z (%): 134 (12), 133 (8), 132 had been isolated from leaves of P. laevigata by the name (9), 131 (27), 116 (19), 113 (21), 108 (13), 88 (22), 71 (65), of 14-deoxyparsonsianine. 14) 60 (26), 43 (100), 41 (29). ^-NMR (D2O) d: 3.00 (1H, d, 7=16.5), 2.77 (1H, d, 7=16.5), 1.93 (1H, septet,.7=6.7), References 0.91 (3H,d, 7=6.7),0.87 (3H, d, 7=6.7). 13C-NMR(D2O) S: 180.62 (C-l), 177.10 (C-4), 80.67 (C-2), 43.66 (C-3), 1) R. Nishida, C. S. KimandH. Fukami, Chemoecology, 37.81 (C-5), 18.74 (C-6), 17.93 (C-6). submitted. Compound 10 (2-ethyl-2,3-dihydroxybutanoic acid). 2) C. C. Culvenor and L. W. Smith, Aust. J. Chem., 19, 1955 (1966). [a]£6 -11° (c=1.4, H2O). EIMS m/z (%): 104 (M+-C2H4O, 100), 89 (53), 86 (18), 85 (20), 58 (ll), 57 3) J. N. Roitman, Aust. J. Chem., 36, 769 (1983). (38), 45 (37), 44 (20), 43 (65), 42 (27). ^-NMR (D2O) S: 4) J. A. Edgar, N. J. Egger, A. J. Jones and G. B. 3.98 (1H, q, 7=6.5), 1.9-1.2 (2H, m), 1.15 (3H, d, 7=6.5), Russell, Tetrahedron Lett., 21, 2657 (1980). 0.83 (3H, t, 7=7.4). 13C-NMR (D2O) S: 180.46 (C-l), 5) F. E. Cole, M. G. Kalyanpur and C. M. Stevens, Biochemistry, 12, 3346 (1973). 84.30 (C-2), 73.79 (C-3), 30.23 (C-5), 18.09 (C-4), 9.64 (C-6). 6) D. J. Robins, Fortschr. Chem. Org. Naturst., 41, 115 (1982). Hydrolysis of4a. In the same manner as that for 3a, 7) F. Abe and T. Yamauchi, Chem. Pharm. Bull., 35, parsonsine (4a) was hydrolyzed to retronecine (6, [a]£6 4661 (1987). +58°, c=0.1, EtOH) and two acids (7 and 8). Acids 7 and 8) J. A. Edgar, M. Boppre and D. Schneider, Experientia, 35, 1447 (1979). 8 were separated by HPLCunder the same conditions as these employed for the isolation of 8 and 10 (7: 9) J. A. Edgar, /. ZooL, Lond., 196, 385 (1982). tR=17.1 min). The optical rotation values for 8 and 10 10) M. Boppre, Naturwissenschaften, 73, 17 (1986). could not be obtained because of their low quantities. ll) R. Nishida, C. S. Kim, K. Kawai and H. Fukami, Compound 7 (trachelanthic acid). EIMS m/z (%): 118 Chem. Express, 5, 497 (1990). (M+-C2H4O, 56), 103 (100), 100 (20), 85 (45), 73 (13), 12) J. R. Trigo and K. S. Brown, Chemoecology, 1, 22 (1990). 71 (13), 57 (32), 56 (26), 45 (17), 43 (45), 41 (10). ^-NMR (D2O) S: 4.07 (1H, q, 7=6.4), 2.03 (1H, septet, 7=6.8), 13) J. A. Edgar, "The Biology of Butterflies," ed. by R. 1.14(3H,d,7=6.4),0.89(6H,d,7=6.8). 13C-NMR(D2O) I. Vane-Wright and P. R. Ackery, Academic Press, S: 85.81 (C-2), 71.40 (C-3), 34.62 (C-5), 19.02 (C-6*), 18.47 New York, 1984, p. 91. (C-4*, C-6). 14) F. Abe, T. Yamauchi, S. YagaandK. Minato, Chem. Pharm. Bull, 39, 1576 (1991).