Dammarane triterpenoids from Dysoxylum richii

Phytochemistry, Vol. 30,No. 3, pp.921-926, 1991 Printedin GreatBritain.

DAMMARANE

0031-9422/91 %3.00+0.00 Q 1991PergamonPressplc

TRITERPENOIDS FROM D YSOX YLUM RICH11 WILLIAM AALBERSBERG and YOGENDRA SINGH

Department of Chemistry, University of the South Pacific, Box 1168, Suva, Fiji

(Receiuedin revised form 25 June 1990) Key Word Index-Dysoxylum

richii;

Meliaceae; fruits; dammarane; triterpenoid; Fijian medicinal plants.

Abstract-Four

new dammarane-type triterpenoids, named methyl richenoate, richenone, richenol and richenoic acid, together with four known triterpenoids, ocotillone, cabraleone, shoreic acid and eichlerianic acid, were isolated from the fruits of Dysoxylum richii. The proposed structures were established by chemical interconversions, spectral analysis and comparisons among closely related compounds.

INTRODUCTION Dysoxylum richii (A. Gray) C. DC. is a leafy timber tree endemic to Fiji which grows in lowland forests. The leaves and bark are used as a medicine by the indigenous people for treating rigid limbs, facial distortion in children, lumps under the skin and other skin irritations, and as a remedy for sexually transmitted diseases [ 11. It is also reportedly used as a remedy for fish poisoning and for convulsions [2]. The chemistry of D. richii has not been previously studied to any great extent except for the report of the presence of dysoxylin, a limonoid from Fijian D. richii leaves [3]. We describe the isolation and structure elucidation of four novel and four known dammarane triterpenoids from the fruits of Fijian D. richii.

RESULTSAND DISCUSSION

The crude petrol-soluble fraction was fractionated and purified to yield eight compounds. Four of these were ultimately identified as the known compounds ocotillone (l), cabraleone (2), shoreic acid (3) and eichlerianic acid (4). The four others are new compounds and have been given the trivial names methyl richenoate (5), richenone (6), richenol(7) and richenoic acid (8). Compound 4 (yield 0.14%) was the major component obtained from the petrol-soluble fraction followed by 8 (O.l%), 3 (0.09%), 1 (0.05%), 2 (0.03%), 7 (0.03%), 6 (0.02%) and 5 (0.01%). Compounds l-4 (reported for the first time from genus Dysoxylum) have been previously isolated from Cabralea eichlerianu [4], Cabralea polytricha [5]. Dipterocarpus hispidus [6], Dryobalanopus sp. [7], Shorea sp. [8,9] and Cowania mexicana [lo]. All eight compounds isolated from the petrol extract had very similar ‘H NMR (Table 1) and “C NMR (Table 2, 3) spectra, showing the presence of a series of structurally similar CJO compounds. Furthermore, these compounds all gave a positive Liebermann-Burchard test indicating the presence of triterpenoids. The structure determination of 8 was carried out first, due to the presence of more alkene NMR resonances. The IR spectrum of 8 showed the presence of carboxylic acid [3500-2600 (br OH), 1710cm-’ (C=O)],

olefinic [3070, 3050cm-I), 1650, 1638, 900, 850 cm-‘(>C=CH,)] and ether (1085 cm-‘) groups. The ‘H NMR spectrum showed four shielded methyls (60.86, 0.89, 1.01, 1.18) and two olefinic methyls (61.71, 1.73). In addition, two multiplets at 62.18 and 2.36, a doublet of doublets at 64.25 (J = 3.4 and 8.9 Hz) and four singlets at 64.66,4.77,4.85 and 4.99, each integrating for one proton, were observed. The doublet of doublets centred at 64.25 indicates the presence of a proton on a carbon bearing an oxygen function and the singlets at 64.66 and 4.77,4.85 and 4.99 suggest the presence of two sets of olefinic methylene protons. Nuclear Overhauser effects on the olefinic methyls by irradiation of the olefinic hydrogens confirmed the presence of two isopropenyl groups. The “C NMR spectrum (Table 3) showed the presence of 30 carbon atoms and confirmed the presence of a carboxylic carbon (6 180.3, s) and two isopropenyl groups whose disubstituted olefinic and the methylene carbons resonate at 6 147.4, s and 113.4, t and at 146.0, s and 110.3, t. Furthermore, downfield signals at 686.6, s and 82.7, d were observed. The assignments of the “C NMR spectral signals of compound 8 were made on the basis of a DEPT experiment [ 1l] and heteronuclear chemical shift-correlated 2D NMR spectrometry. Short-range and long-range hetero and homo COSY spectra indicated a seco-A-ring and ring structure identical to that found in eichlerianic acid (4) and shoreic acid (3), the isopropanol group substituted on C-24 having been dehydrated to the isopropenyl group. The resonance visible at 6 2.18 as a one-proton multiplet is characteristic of H-17 of dammarane type triterpenes [13]. Furthermore, the signals at 686.6, s and 82.7, d were observed to be typical of C-20 and C-24 in the 20,24-epoxy dammaranes reported earlier [12]. The stereochemistry of the methyl group at C-20 and of H-24 was determined by comparison of the 13C NMR spectrum of 8 with that of ocotillone (1) and cabraleone (2) previously reported [13]. The structures of 1 and 2 given by Tanaka and Yahara [12] and Rao et al. [4] have been revised on the basis of X-ray crystallographic analysis [14]. The C-24 having a /I-proton resonated at ca 687 and that having an u-proton resonated at ca 684. The signal assigned to C-24 in compound 8 resonated at 682.7, indicating the presence of an u-proton at C-24. 921

W. AALBERSBERG and Y. SINGH

922

OH

OH

5 8

R = Me

6

R=H

HO 7

Hence, compound 8 isolated from the fruits of D. richii is assigned the structure shown and named richenoic acid. The El HR mass spectrum of compound 8 had [M]’ at m/z 456.3591 (dev 1.2 mmu) for C,, H,,Oz with the base peak at m/z 125 (CsH,,O). Fragments with m/z 235,221 and 161 were also observed. The base peak at m/z 125 may be due to a tetrahydrofuryhsopropenyl group. The peak at m/z 235 is attributable to ion 9 (Scheme l), which on methylene loss leads to the fragment at m/z 221 (10).The mass spectral data (fragment ions with m/z 235, 221 and 161) of compound 8 are in accord with that of the 3,4-seco-triterpenoids, shoreic acid (3) and eichlerianic acid (4), reported earlier [lo]. In the mass spectra of 3 and 4 the base peak was observed at m/z 143 corresponding to

the tetrahydrofurylisopropanol ion (11).The base peak at m/z 125 (C,Hi30) for 8 corresponds to m/z Cl43 -Hz01 supporting the presence of the tetrahydrofurylisopropenyl side chain in the molecule. The presence of the tetrahydrofuryhsopropenyl group in 8 was further supported by the absence of a peak at m/z 59 [Me,C=O]+ observed in the mass spectra of 3 and 4. The presence of a carboxylic acid group was established by methylation with ethereal diazomethane producing the methyl ester 5 [IR: no OH absorption, 1738cm-i (-COzMe); ‘H NMR: 63.67 (3H, s); 13C NMR: 6174.6 (-QO,Me), 51.7 (-CO,Me), El HRMS m/z 470.3762 (dev. 0.3 mmu)]. The methyl ester 5, methyl richenoate, was also isolated as a natural product (identical IR, ‘H NMR,

Dammarane triterpenoids from Dysoxylum richii

923

“02c!1 HO&!! m/z 235

m/z 221

9

10

m/z 143

m/z 125

m/z 99

Scheme 1. Prominent fragment ions observed in the mass spectra of dammarane type triterpenes.

13C NMR and EIMS with synthetic methyl richenoate) it may be an artifact formed during the long extraction period in methanol, but this was not tested. Compound 4 was also a carboxylic acid with ‘H and r3C NMR resonances characteristic of the dammarane skeleton. An added feature was a tertiary carbon with resonance at 672.5 in the r3C NMR spectrum. The previously isolated eichlerianic acid [lo] had properties identical to those of the compound 4 isolated. This structure corresponds to addition of water to the isoprenyl group on C-24 of compound 8. The signal at 63.73 (t, 5=7.1 Hz) in the ‘H NMR spectrum is characteristic of H-24 of compounds having the tetrahydrofurylisopropan01 group. Compound 3 had identical spectral properties with 4 except that a 13C NMR resonance appeared at 6 86.1 instead of 83.3 and a multiplet at 63.68 instead of a triplet at 3.71 was observed in the ‘HNMR spectrum. This indicated 3 was the C-24 (R) epimer of 4, the previously isolated shoreic acid [12]. Compounds 1 and 2 also had spectral properties that indicated them to be epimers at C-24. The methylene and carboxylic acid groups of the seco-ring A were no longer present. Instead a keto and two methyl groups were present indicating closure of the A ring. Compounds 1 and 2 were identified with the known ocotillone and cabraleone [4, 12, 143 by their spectral and physical properties as well as those of their acetates. Compound 6 was also a ketone (6218.2 in “C NMR) and showed resonances of a dammarane skeletal pattern. One isopropenyl group was present with no alcohol or acid group present. Irradiation of H-24, which resonated at 64.24, included nuclear Overhauser effects on the alkene protons at 64.78 and 5.00 and the methyl at 1.71, showing that the isopropenyl group was attached at C-24 as in 8. The resonance at 6 82.8 also indicates the same Sstereochemisty. Thus, 6 was identified as the dehydrated analogue of 2 and named richenone. Compound 7 differed from compound 6 only in the absence of a ketone and

924 Table

W. AALBERSBERGand Y. SINGH

2. 13C NMR spectral data for compounds (75.46 MHz, &values, CDCI,)

C

8

1

24.6 34.2 180.3 147.4 41.1 31.3 33.8 39.9 49.7 40.0 22.2 25.6 43.0 50.3 31.3 26.7 50.8 15.3 20.1 86.6 26.1 35.5 28.3 82.7 146.4 110.3 17.8 113.4 23.2 16.2

2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 CO,Me

5

t t s s d

t t s d s

t t d s

t t d

q q s

q

t t d s

t q

t q q

24.7 t 34.5 t 174.6 s 147.6 s 41.0 d 31.3 t 34.0 t 39.2 s 50.0 d 41.1 s 22.3 t 25.7 t 43.1 d 50.4 s 31.3 t 26.8 t 51.0d 15.49 20.1 q 86.7 s 26.3 q 35.4 t 28.4 t 83.0 d 146.4 s 110.3 t 17.2 q 113.6 t 23.2 q 16.2 q 51.7 q

4

3 24.4 28.1 179.2 147.2 41.0 31.2 33.7 39.9 49.5 38.9 22.1 25.6 42.7 50.2 23.8 26.7 50.7 15.1 19.9 86.3 26.1 34.7 26.8 86.1 70.1 26.8 27.6 113.2 22.9 16.1

8, 5, 3 and 4

d t s s d

t t s d s

t t d s

t t d

q q s

q

t t d s

q q

t q q

24.6 34.3 179.4 147.5 41.1 31.5 33.9 40.0 49.5 39.1 22.1 25.6 43.0 50.4 31.5 27.2 50.8 15.3 20.1 86.4 23.5 35.8 26.1 83.3 71.5 24.2 27.4 113.4 23.2 16.3

t t s s d

1 t s d s

t t

d s

t t d q q s

q

t t d s

q q

t q q

the presence instead of a secondary hydroxy group [‘H NMR 63.20dd (J=5.4 Hz, 10.6 Hz), 13C NMR 678.6 d]. The presence of a hydroxyl group was confirmed by acetylation with acetic anhydride-pyridine producing the monoacetate 15 [IR: no OH absorption, 1728 cm- ’ (OAc); ‘H NMR: 62.04 3H, s, OAc)]. The ‘H NMR spectrum of 15 also showed that the proton resonating at 63.20 in 6 had undergone an acetylation shift from 63.20 in 6 to 64.48 in the acetate. The acetate of 7 was identical to the acetate formed by the acetylation of the sodium borohydride reduction product of 6, showing that compound 7, named richenol, was the reduction product of richenone (6). The hydroxyl group at C-3 is equatorially oriented as the doublet of doublets centred at 63.20 and it is characteristic of a proton attached to the carbon carrying a /3-hydroxyl group [S]. The structure of compound 7 was also verified by oxidation with Sarett’s reagent to richenone (6). The dammarane-type triterpenes from D. richii fruits were tested for bactericidal and fungicidal activities and against the growth of Lemna minor. They have been found to be active at concentrations of 25 pgml- ’ against the growth of bacteria and Lemna. Compounds 5, 6 and 8 inhibited the growth of both the bacteria Staphylococcus aureus and Bacillus subtilis. However, compounds 7, 1,2, 3 and 4 were only active against the growth of Bacillus

Table

3. 13C NMR spectral data for compounds (75.46 MHz, &values, CDCI,)

C

6

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

39.2 34.1 218.2 47.4 55.3 19.7 34.6 40.3 49.8 36.7 22.3 25.8 43.1 50.0 31.4 26.9 50.1 15.3 16.2 86.6 26.6 35.2 26.9 82.8 146.2 110.4 17.8 26.8 21.0 16.2

7

t t s s

d t

t s

d s t

t d s

t t d q q s q

t t

d s

t q q 4 q

39.1 27.4 78.9 39.0 55.9 18.3 35.3 40.4 50.8 37.2 21.7 25.8 42.9 50.0 31.3 26.9 49.9 15.5 16.2 86.6 26.5 31.4 35.2 82.8 146.3 110.3 17.8 15.3 28.0 16.0

1

t t s s

d t

t s

d s

t t

d s

t t d q q s q

t t d s

t q q

q q

39.9 34.1 218.1 47.4 55.4 19.7 34.8 40.3 49.8 36.9 22.3 25.8 43.0 50.0 31.4 27.0 50.2 16.1 15.2 86.5 24.1 34.6 26.4 86.4 70.3 26.8 27.2 27.8 21.0 16.3

6, 7, 1 and 2

2 t t s s

d

t t s

d s

t t d s

t t d q

q s

q

t t d s q

q q q q

39.9 t 34.1 t 217.9 s 47.4 s 55.6 d 19.7 t 34.7 t 40.4 s 49.6 d 36.9 s 22.1 t 26.2 t 43.2 d 50.1 s 31.5 t 27.4 t 50.2 d 16.0 q 15.29 86.3 s 23.6 q 35.8 t 27.5 t 83.4 d 71.4 s 25.7 q 26.8 q 26.8 q 21.09 16.4 q

subtilis and Lemna.

The use of D. richii in Fiji as a medicinal plant may be due to the presence of these dammarane triterpenes. Although this paper only reports work on the fruit extract, work in our laboratory has also isolated these compounds from the leaves, which are used medicinally. A large number of naturally occurring seco-A-derivatives [15, 161 as well as synthetic compounds with a 3,4seco-3-acid structure (derived from steroids and tetracyclic and pentacyclic triterpenes), have been reported to be highly antibacteriai [17, 181. The 3,4-seco-triterpenes have been reported in plants renowned in folk medicine [19-211 and this work provides further evidence.

EXPERIMENTAL All mps: uncorr. TLC and VLC were carried out using silica gel. HPLC was performed using a silica gel column (200 x 5 mm i.d.) using EtOAc-petrol(3: 7) at 800 psi and with refractive index detection. ‘H NMR spectra were recorded at 300 MHz in CDCI, using TMS as int. standard. 13C NMR were recorded at 75 MHz in CDCI, with TMS as int. standard. Plunt material. Dysoxylum richii (A. Gray) C. DC. fruits were collected in October 1985 from Mount Korobaba near Lami on the island of Viti Levu in the Fiji Islands. (A voucher specimen is

Dammarane triterpenoids from Dysoxylum richii held at the South Pacific Regional Herbarium, University of the South Pacific, Suva, Fiji.) Extraction and isolation of the components from Dyxosylum richiifruits. Freshly collected fruits (3.6 kg) were crushed using a grinder in the presence of MeOH and the resulting slurry was allowed to stand at 10” for 3 months in 10 1MeOH. The mixt. was stirred manually at 5 day intervals. The soln was filtered, coned under red. pres. to ca 200 ml and diluted with Hz0 (600 ml). This mixt. was then extracted with petrol (5 x 200 ml). Concn of the petrol solubles in uacuo gave 45.59 g (yield 1.27%) of a yellowish-green gummy syrup. This syrup was fractionated using vacuum liquid chromatography (VLC) with step gradient elution using petrol, EtOAc and MeOH [22,23]. The frs eluted were subjected to further VLC and final purification, if necessary, was performed by HPLC. In terms of increasing polarity the compounds eluted in the order 5,6,7, 1,2, g, 3 and 4. Ocotillone (1). Solid (481 mg) mp: 164-165” (lit. 163-166.5”) [a]:’ 59” (CHCl,; ~0.7) (lit. +60”) [4]. Cabraleone (2). Solid (835 mg) mp: 159-160” (lit. 160-161”) [ali 54” (CHCI,; c 1.0) (lit. +54”) [S]. Shoreic acid (3). Solid (873 mg) mp: 103-104” (lit. 102-104”) [a]h5 + 38” (CHCl,; c 1.0) (lit. + 38.4”) [lo]. Eichlerianic acid (4). Oil (1.37 g), [ali +41” (CHCl,; ~0.96) (lit. +40”) [lo]. Methyl (20S,24S)-epoxy-25(26)-en-3,4-seco-4(28) dammaren-3oate (5). Oil (478 mg). HRMS [Ml+ at m/z 470.3762 (dev.

0.3 mmu). IR Y,,, cm-‘: no OH absorption, 3070, 2960, 2870, 1738 (-CO,Me), 1636,1455,1375, 1340,1280,1215,1170,1120, 1090, 1045, 1025, 890,870; ‘H NMR (CDCI,, 400 MHz): 60.86 (3H,s),O.Q0(3H,s), l.O3(3H, s), l.l8(3H,s), 1.73(3H, s), 1.75(3H, s) 3.67 (3H, s), 4.25 (lH, dd, J=3.3 Hz, J=8.8 Hz), 4.67 (lH, s), 4.74 (lH, s), 4.87 (lH, s), 5.00 (lH, s); ‘“CNMR (CDCI,, 75.46 MHz): (Table 2) EIMS m/z (% rel. int.): 470 [M]’ (I), 452 [M-HzO]+ 0.6, 439 [M-OMe]+ 0.3, 384 [M-C,H,Oz]+ (l), 343 CM-C,H1,0J+ (lb 249 CM-C,,H,,OI+ W, 175 [M-C,,H,,O-C,H,O,]+ (3), 161 [M-C15H,,0 -C,H,O,]+(4), 149 [M-Cz,,Ho303]+ (13), 147 [M -CisHz,O-C4Hs02-j+ (4), 125 [CsH130]+ (lOO), 107 CWWI + (15). (20S,24S)-Epoxy-25(26)-ene-dammaran-3-one (6). Needles (754mg) mp l&141” [a]:: + 57”(CHCl,; cO.O3), HRMS [MJ’ m/z 440.3661 (dev. 0.7 mmu) IR v:; cm-‘: 3080, 2950, 2862, 1700 (C=O), 1650 (C=C), 1455, 1385, 1340, 1310, 1265, 1210,1180,1160,1155,1085 (C-O-c), 1040,1020,980,965,955, 910 br, 870, 835, 805 (olefinic C-H); ‘HNMR (CDCI,, 300 MHz): 60.88(3H, s),0.94(3H, s), l.O1(3H, s), l.O4(3H, s), 1.08 (3H, s), 1.17 (3H, s), 1.71 (3H, s), 2.46 (2H, m), 4.24 (lH, dd, J= 3.3 Hz, J=8.9 Hz), 4.78 (lH, s), 5.00 (lH, s); 13C NMR (CDCl,, 75.46 MHz): (Table 3); EIMS m/z (% rel. int.): 440 [M]’ 0.2,425 [M-Me]+ 0.2, 342 [M-C,H,,O]+ (l), 315 [M-C,H,,O]’ (0.6), 245 [M-C,,H,,O]+ (2), 219 [M-C,,H,,O]+ (2), 205 CM-G~H~,01+ (4), 161 CM-‘%&W+(5), 147 CM -C&33021+(7), 125CGHnOl+ WV, 107CGH,OI+ W, 93[C,H,O]’ (10); reduction of 6 with NaBH, in MeOH gave a compound with identical mp, mmp and spectral data as 7. (20S,24S)-Epoxy-25(26)-en-dammaran-3-o1 Needles (7). (214 mg) mp 146147”, IRvifi cm-‘: 3440 (OH), 3080, 2925, 2865,1650(C=C), 1450,1385,1375,1305,1240,1215,1165,1140, 1120, 1080 (C-@C), 1040, 1020, 980, 945, 900, 870 (olefinic C-H); ‘H NMR (CDCI,, 300 MHz): 6 0.77 (3H, s), 0.85 (3H, s), 0.87 (3H, s), 0.97 (3H, s). 1.17 (3H, s), 1.58 (3H, s), 1.71 (3H, s) 3.20 (lH, dd, J=5.4Hz, 5=10.6Hz), 4.24 (lH, dd, J=3.3Hz, J=8.9Hz), 4.77 (lH, s), 4.99 (lH,s); ‘jCNMR (CD&, 75.46 MHz) (Table 2); EIMS m/z (% rel. int.): 442 [M]’ (2), 424 [M-H,O]+ (l), 317 [M-CsH130]+ (I), 203 [M-C,,H,,O,I+ (21, 189 CM-C,&,OJ+ (81, 175

925

@), 161 CM-%JLW+(6h CM CM-C,JWM+ -C,gH330,]+ (Q),147[M-C 19H 350 2]+ (5), 125 [CBHlaO]+ (lOO), 107 [C,H,O]+ (20), 95 &,H,O]+ (14); acetylation of 7 with Ac,O in pyridine gave an oil. IRv,,, cm- ‘: no OH, 1728 (OAc); ‘H NMR (CDCl,, 270 MHz): 6 0.85 (3H, s), 0.87 (3H, s), 0.89 (3H, s),O.Q9(3H, s), 1.17 (3H, s), 1.25 (3H, s), 1.71(3H, s), 2.04 (3H, s), 4.24 (lH, dd, J=3.4, 8.9Hz), 4.48 (lH, dd, 5=5.0, 10.1 Hz), 4.78 (lH, s), 4.99 (lH, s); oxidation of 7 with CrO, in pyridine gave a compound with identical mp, mmp and spectral data as 6. (20S,24S)-Epoxy-25(26)-en-3,4-seco-4(28)-dammaren-3-oic acid (8). Solid (2.31 g) crystallized from petrol-EtOAc (8:2), mp

15%161”, [a]ks 0” (CHCl,, c 0.005); IRv!$ cm-‘: 3500-2660 (OH), 3070, 3050, 2970, 2862, 1710 (C=O), 1650, 1638 (C=C), 1455,1375,1322 br (C-O acid), 1195,1155,1085 (C-O-C), 1040, 1018, 985, 955, 900 br, 850 (olefinic C-H); ‘H NMR (CDCl,, 300 MHz): a0.86(3H, s),0.89(3H, s), l.O1(3H, s), l.l8(3H,s), 1.71 (3H,s),1.73(3H,s),2.18(1H,m),2.36(1H,m),4.25(1H,dd,J=3.4, 8.9 Hz), 4.66 (lH,s), 4.77 (lH,s), 4.85 (lH,s), 4.99 (lH, s); 13C NMR (CDCI,, 75.46 MHz): (Table 2); EIMS m/z (% rel. int.): 456 [M]’ (2), 441 [M-Me]+ (l), 343 [M-C,H,O,]+(l), 249 [M-C14Hz30]+ (l), 235 [M-C,,H,,O]+ (I), 221 [M-C16H2,0]+ (l), 175 [M-C,,HZ30-C,H60z]+ (3), 161 147 [M-C16H,,0 CM--GSH,,O-C~-&W+ (3), -C,H,O]+(4), 125 [CsH130]+ (lOO), 107 [C,H,O]+ (20). HRMS [M]’ (m/z) 456.3591 (dev. 1.2 mmu), methylation of 8 with diazomethane gave a compound with identical spectral properties as 5. Acknowledgements-Plant amples were collected by Saula Vodonaivalu of the South Pacific Regional Herbarium. We are grateful to Dr John Coil (James Cook), and Dr Raymond Anderson (British Columbia) for spectral data and Mr Mike Le Blanc (British Columbia) for bioassays. The research was supported by a grant from the University of the South Pacific Research Committee. Yogendra Singh thanks the Davidson Fund Committee, the Australian University IDP Program and the Network for the Chemistry of Biologically Important Natural Products for further support.

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W. AALBERSBERG and Y. SINGH

926

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