Exact Mass: 636.2512
Exact Mass Matches: 636.2512
Found 57 metabolites which its exact mass value is equals to given mass value 636.2512
,
within given mass tolerance error 0.01 dalton. Try search metabolite list with more accurate mass tolerance error
0.001 dalton.
Calix[6]arene
heptacyclo[31.3.1.1^{3,7}.1^{9,13}.1^{15,19}.1^{21,25}.1^{27,31}]dotetraconta-1(37),3,5,7(42),9,11,13(41),15(40),16,18,21(39),22,24,27(38),28,30,33,35-octadecaene-37,38,39,40,41,42-hexol
Styraxlignolide A
2-{3-[2-(3,4-dimethoxyphenyl)-7-methoxy-1-benzofuran-5-yl]propoxy}-6-{[(3,4,5-trihydroxyoxan-2-yl)oxy]methyl}oxane-3,4,5-triol
1,2,6-Triacetoxy-9,14-dibenzoyloxydihydro-alpha-agarofuran
1,2,6-Triacetoxy-9,14-dibenzoyloxydihydro-alpha-agarofuran
1alpha,6beta,15-triacetoxy-2alpha,9beta-dibenzoyloxydihydro-beta-agarofuran|1beta,6alpha,15-triacetoxy-2beta,9alpha-dibenzoyloxydihydro-beta-agarofuran|elat-1
1alpha,6beta,15-triacetoxy-2alpha,9beta-dibenzoyloxydihydro-beta-agarofuran|1beta,6alpha,15-triacetoxy-2beta,9alpha-dibenzoyloxydihydro-beta-agarofuran|elat-1
(1R,2S,3S,4S,5S,6R,7R,9S,10R)-2,3-diacetoxy-1-benzoyloxy-9-trans-cinnamoyloxy-4,6-dihydroxydihydro-beta-agarofuran
(1R,2S,3S,4S,5S,6R,7R,9S,10R)-2,3-diacetoxy-1-benzoyloxy-9-trans-cinnamoyloxy-4,6-dihydroxydihydro-beta-agarofuran
6-O-acetylpseudolaric acid B-O-beta-D-glucopyranoside
6-O-acetylpseudolaric acid B-O-beta-D-glucopyranoside
(1alpha,2alpha,8beta,9beta)-1,8,14-tris(acetyloxy)-2,9-bis(benzoyloxy)-beta-dihydroagarofuran
(1alpha,2alpha,8beta,9beta)-1,8,14-tris(acetyloxy)-2,9-bis(benzoyloxy)-beta-dihydroagarofuran
(1R,2S,3S,4S,5S,6R,7R,9S,10R)-1-benzoyloxy-9-cinnamoyloxy-2,6-diacetoxy-3,4-dihydroxy-dihydro-beta-agarofuran
(1R,2S,3S,4S,5S,6R,7R,9S,10R)-1-benzoyloxy-9-cinnamoyloxy-2,6-diacetoxy-3,4-dihydroxy-dihydro-beta-agarofuran
8alpha-acetoxy-11beta,13-dihydroglucozaluzanin C pentaacetate
8alpha-acetoxy-11beta,13-dihydroglucozaluzanin C pentaacetate
Glu Tyr Tyr Tyr
(4S)-4-amino-4-{[(1S)-1-{[(1S)-1-{[(1S)-1-carboxy-2-(4-hydroxyphenyl)ethyl]carbamoyl}-2-(4-hydroxyphenyl)ethyl]carbamoyl}-2-(4-hydroxyphenyl)ethyl]carbamoyl}butanoic acid
Tyr Glu Tyr Tyr
(4S)-4-[(2S)-2-amino-3-(4-hydroxyphenyl)propanamido]-4-{[(1S)-1-{[(1S)-1-carboxy-2-(4-hydroxyphenyl)ethyl]carbamoyl}-2-(4-hydroxyphenyl)ethyl]carbamoyl}butanoic acid
Tyr Tyr Glu Tyr
(4S)-4-[(2S)-2-[(2S)-2-amino-3-(4-hydroxyphenyl)propanamido]-3-(4-hydroxyphenyl)propanamido]-4-{[(1S)-1-carboxy-2-(4-hydroxyphenyl)ethyl]carbamoyl}butanoic acid
Tyr Tyr Tyr Glu
(2S)-2-[(2S)-2-[(2S)-2-[(2S)-2-amino-3-(4-hydroxyphenyl)propanamido]-3-(4-hydroxyphenyl)propanamido]-3-(4-hydroxyphenyl)propanamido]pentanedioic acid
Calix[6]arene
Heptacyclo[31.3.1.13,7.19,13.115,19.121,25.127,31]dotetraconta-1(37),3,5,7(42),9,11,13(41),15,17,19(40),21,23,25(39),27,29,31(38),33,35-octadecaene-37,38,39,40,41,42-hexol
9-[1,1-Biphenyl]-3-yl-9-[1,1-biphenyl]-4-yl-3,3-bi-9H-carbazole
9-[1,1-Biphenyl]-3-yl-9-[1,1-biphenyl]-4-yl-3,3-bi-9H-carbazole
N-[4-[(2,3-dihydroxybenzoyl)amino]butyl]-N-[3-[(2,3-dihydroxybenzoyl)amino]propyl]-2-(2,3-dihydroxyphenyl)-5-methyl-4,5-dihydro-1,3-oxazole-4-carboxamide
N-[4-[(2,3-dihydroxybenzoyl)amino]butyl]-N-[3-[(2,3-dihydroxybenzoyl)amino]propyl]-2-(2,3-dihydroxyphenyl)-5-methyl-4,5-dihydro-1,3-oxazole-4-carboxamide
N-[(2R,3R)-2-[[(4-fluorophenyl)sulfonyl-methylamino]methyl]-5-[(2R)-1-hydroxypropan-2-yl]-3-methyl-6-oxo-3,4-dihydro-2H-1,5-benzoxazocin-8-yl]-2-(1-methyl-3-indolyl)acetamide
N-[(2R,3R)-2-[[(4-fluorophenyl)sulfonyl-methylamino]methyl]-5-[(2R)-1-hydroxypropan-2-yl]-3-methyl-6-oxo-3,4-dihydro-2H-1,5-benzoxazocin-8-yl]-2-(1-methyl-3-indolyl)acetamide
(2R,3R,4R,5S)-3-[(2S,3R,4S,5R,6R)-4,5-Dihydroxy-6-(hydroxymethyl)-3-[(2S,3S,4R,5S,6S)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-4-[(2S,3S,4R,5S,6S)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyhexane-1,2,5,6-tetrol
(2R,3R,4R,5S)-3-[(2S,3R,4S,5R,6R)-4,5-Dihydroxy-6-(hydroxymethyl)-3-[(2S,3S,4R,5S,6S)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-4-[(2S,3S,4R,5S,6S)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyhexane-1,2,5,6-tetrol
[(1s,2s,5s,6s,7s,9r,12r)-5-(acetyloxy)-6-[(acetyloxy)methyl]-2,12-dihydroxy-2,10-dimethyl-7-{[(2e)-3-phenylprop-2-enoyl]oxy}-11-oxatricyclo[7.2.1.0¹,⁶]dodecan-10-yl]methyl benzoate
[(1s,2s,5s,6s,7s,9r,12r)-5-(acetyloxy)-6-[(acetyloxy)methyl]-2,12-dihydroxy-2,10-dimethyl-7-{[(2e)-3-phenylprop-2-enoyl]oxy}-11-oxatricyclo[7.2.1.0¹,⁶]dodecan-10-yl]methyl benzoate
[(8r,9s,10s,12r,13s,14s,16s,17s,19r,20s,21r,22s)-9,16,21,22-tetrahydroxy-5-(hydroxymethyl)-13,20,25-trimethyl-4,24-dioxo-3,23-dioxanonacyclo[14.10.1.0²,⁶.0²,¹⁴.0⁸,¹³.0¹⁰,¹².0¹⁷,¹⁹.0²⁰,²⁷.0²²,²⁶]heptacosa-1(27),5,25-trien-9-yl]methyl (2e)-2-methylbut-2-enoate
[(8r,9s,10s,12r,13s,14s,16s,17s,19r,20s,21r,22s)-9,16,21,22-tetrahydroxy-5-(hydroxymethyl)-13,20,25-trimethyl-4,24-dioxo-3,23-dioxanonacyclo[14.10.1.0²,⁶.0²,¹⁴.0⁸,¹³.0¹⁰,¹².0¹⁷,¹⁹.0²⁰,²⁷.0²²,²⁶]heptacosa-1(27),5,25-trien-9-yl]methyl (2e)-2-methylbut-2-enoate
(1s,2r,4s,5r,6r,7s,9r,12r)-5,12-bis(acetyloxy)-6-[(acetyloxy)methyl]-4-(benzoyloxy)-2,10,10-trimethyl-11-oxatricyclo[7.2.1.0¹,⁶]dodecan-7-yl benzoate
(1s,2r,4s,5r,6r,7s,9r,12r)-5,12-bis(acetyloxy)-6-[(acetyloxy)methyl]-4-(benzoyloxy)-2,10,10-trimethyl-11-oxatricyclo[7.2.1.0¹,⁶]dodecan-7-yl benzoate
4,8,15,19,26,30-hexahydroxy-1,12-dithia-4,9,15,20,26,31-hexaazacyclotritriaconta-8,19,30-triene-5,16,27-trione
4,8,15,19,26,30-hexahydroxy-1,12-dithia-4,9,15,20,26,31-hexaazacyclotritriaconta-8,19,30-triene-5,16,27-trione
5,12-bis(acetyloxy)-6-[(acetyloxy)methyl]-4-(benzoyloxy)-2,10,10-trimethyl-11-oxatricyclo[7.2.1.0¹,⁶]dodecan-7-yl benzoate
5,12-bis(acetyloxy)-6-[(acetyloxy)methyl]-4-(benzoyloxy)-2,10,10-trimethyl-11-oxatricyclo[7.2.1.0¹,⁶]dodecan-7-yl benzoate
(1s,2s,3s,4s,5r,6r,7s,9r,12r)-3,4-bis(acetyloxy)-2,12-dihydroxy-2,6,10,10-tetramethyl-7-{[(2e)-3-phenylprop-2-enoyl]oxy}-11-oxatricyclo[7.2.1.0¹,⁶]dodecan-5-yl benzoate
(1s,2s,3s,4s,5r,6r,7s,9r,12r)-3,4-bis(acetyloxy)-2,12-dihydroxy-2,6,10,10-tetramethyl-7-{[(2e)-3-phenylprop-2-enoyl]oxy}-11-oxatricyclo[7.2.1.0¹,⁶]dodecan-5-yl benzoate
[(3ar,4r,5r,7ar)-4-[(1ar,2r,3r,3ar,4r,5r,6r,7as)-2,5-dihydroxy-3-[(5s)-5-hydroxy-2-oxo-5h-furan-3-yl]-4-{[(2r)-2-hydroxy-3-methylbutanoyl]oxy}-3a-methyl-7-methylidene-hexahydroindeno[1,7a-b]oxiren-6-yl]-4,7a-dimethyl-2-oxo-tetrahydrofuro[2,3-c]pyran-5-yl]acetic acid
[(3ar,4r,5r,7ar)-4-[(1ar,2r,3r,3ar,4r,5r,6r,7as)-2,5-dihydroxy-3-[(5s)-5-hydroxy-2-oxo-5h-furan-3-yl]-4-{[(2r)-2-hydroxy-3-methylbutanoyl]oxy}-3a-methyl-7-methylidene-hexahydroindeno[1,7a-b]oxiren-6-yl]-4,7a-dimethyl-2-oxo-tetrahydrofuro[2,3-c]pyran-5-yl]acetic acid
(1s,2s,4r,5s,6r,7r,9r,12r)-4,5,12-tris(acetyloxy)-6-[(benzoyloxy)methyl]-2,10,10-trimethyl-11-oxatricyclo[7.2.1.0¹,⁶]dodecan-7-yl benzoate
(1s,2s,4r,5s,6r,7r,9r,12r)-4,5,12-tris(acetyloxy)-6-[(benzoyloxy)methyl]-2,10,10-trimethyl-11-oxatricyclo[7.2.1.0¹,⁶]dodecan-7-yl benzoate
n-{3-[n-(4-{[(2,3-dihydroxyphenyl)(hydroxy)methylidene]amino}butyl)-1-[(4s,5r)-2-[(1z)-5-hydroxy-6-oxocyclohexa-2,4-dien-1-ylidene]-5-methyl-1,3-oxazolidin-4-yl]formamido]propyl}-2,3-dihydroxybenzenecarboximidic acid
n-{3-[n-(4-{[(2,3-dihydroxyphenyl)(hydroxy)methylidene]amino}butyl)-1-[(4s,5r)-2-[(1z)-5-hydroxy-6-oxocyclohexa-2,4-dien-1-ylidene]-5-methyl-1,3-oxazolidin-4-yl]formamido]propyl}-2,3-dihydroxybenzenecarboximidic acid
4-methoxy-3-(4-{[(5s)-4-[(6-methoxy-2-methyl-1-oxo-3,4-dihydroisoquinolin-7-yl)oxy]-6-methyl-2h,5h,7h,8h-[1,3]dioxolo[4,5-g]isoquinolin-5-yl]methyl}phenoxy)benzaldehyde
4-methoxy-3-(4-{[(5s)-4-[(6-methoxy-2-methyl-1-oxo-3,4-dihydroisoquinolin-7-yl)oxy]-6-methyl-2h,5h,7h,8h-[1,3]dioxolo[4,5-g]isoquinolin-5-yl]methyl}phenoxy)benzaldehyde
(1s,2s,4s,5r,6s,7r,8s,9s,12r)-4,5-bis(acetyloxy)-2,12-dihydroxy-2,6,10,10-tetramethyl-8-{[(2e)-3-phenylprop-2-enoyl]oxy}-11-oxatricyclo[7.2.1.0¹,⁶]dodecan-7-yl benzoate
(1s,2s,4s,5r,6s,7r,8s,9s,12r)-4,5-bis(acetyloxy)-2,12-dihydroxy-2,6,10,10-tetramethyl-8-{[(2e)-3-phenylprop-2-enoyl]oxy}-11-oxatricyclo[7.2.1.0¹,⁶]dodecan-7-yl benzoate
[(2r,3r,4s,5r,6r)-6-{[(3s,3ar,4s,6ar,8s,9ar,9br)-4-(acetyloxy)-3-methyl-6,9-dimethylidene-2-oxo-octahydro-3h-azuleno[4,5-b]furan-8-yl]oxy}-3,4,5-tris(acetyloxy)oxan-2-yl]methyl acetate
[(2r,3r,4s,5r,6r)-6-{[(3s,3ar,4s,6ar,8s,9ar,9br)-4-(acetyloxy)-3-methyl-6,9-dimethylidene-2-oxo-octahydro-3h-azuleno[4,5-b]furan-8-yl]oxy}-3,4,5-tris(acetyloxy)oxan-2-yl]methyl acetate
{4-[2,5-dihydroxy-3-(5-hydroxy-2-oxo-5h-furan-3-yl)-4-[(2-hydroxy-3-methylbutanoyl)oxy]-3a-methyl-7-methylidene-hexahydroindeno[1,7a-b]oxiren-6-yl]-4,7a-dimethyl-2-oxo-tetrahydrofuro[2,3-c]pyran-5-yl}acetic acid
{4-[2,5-dihydroxy-3-(5-hydroxy-2-oxo-5h-furan-3-yl)-4-[(2-hydroxy-3-methylbutanoyl)oxy]-3a-methyl-7-methylidene-hexahydroindeno[1,7a-b]oxiren-6-yl]-4,7a-dimethyl-2-oxo-tetrahydrofuro[2,3-c]pyran-5-yl}acetic acid
[(2r,8r,9s,10s,12r,13s,14s,16s,17s,19r,20s,21r,22s)-9,16,21,22-tetrahydroxy-5-(hydroxymethyl)-13,20,25-trimethyl-4,24-dioxo-3,23-dioxanonacyclo[14.10.1.0²,⁶.0²,¹⁴.0⁸,¹³.0¹⁰,¹².0¹⁷,¹⁹.0²⁰,²⁷.0²²,²⁶]heptacosa-1(27),5,25-trien-9-yl]methyl (2e)-2-methylbut-2-enoate
[(2r,8r,9s,10s,12r,13s,14s,16s,17s,19r,20s,21r,22s)-9,16,21,22-tetrahydroxy-5-(hydroxymethyl)-13,20,25-trimethyl-4,24-dioxo-3,23-dioxanonacyclo[14.10.1.0²,⁶.0²,¹⁴.0⁸,¹³.0¹⁰,¹².0¹⁷,¹⁹.0²⁰,²⁷.0²²,²⁶]heptacosa-1(27),5,25-trien-9-yl]methyl (2e)-2-methylbut-2-enoate
3,4-bis(acetyloxy)-2,12-dihydroxy-2,6,10,10-tetramethyl-7-[(3-phenylprop-2-enoyl)oxy]-11-oxatricyclo[7.2.1.0¹,⁶]dodecan-5-yl benzoate
3,4-bis(acetyloxy)-2,12-dihydroxy-2,6,10,10-tetramethyl-7-[(3-phenylprop-2-enoyl)oxy]-11-oxatricyclo[7.2.1.0¹,⁶]dodecan-5-yl benzoate
4,5,12-tris(acetyloxy)-6-[(benzoyloxy)methyl]-2,10,10-trimethyl-11-oxatricyclo[7.2.1.0¹,⁶]dodecan-7-yl benzoate
4,5,12-tris(acetyloxy)-6-[(benzoyloxy)methyl]-2,10,10-trimethyl-11-oxatricyclo[7.2.1.0¹,⁶]dodecan-7-yl benzoate
[3,4,5-tris(acetyloxy)-6-{[4-(acetyloxy)-3-methyl-6,9-dimethylidene-2-oxo-octahydro-3h-azuleno[4,5-b]furan-8-yl]oxy}oxan-2-yl]methyl acetate
[3,4,5-tris(acetyloxy)-6-{[4-(acetyloxy)-3-methyl-6,9-dimethylidene-2-oxo-octahydro-3h-azuleno[4,5-b]furan-8-yl]oxy}oxan-2-yl]methyl acetate
(1s,2r,4s,5r,6r,7s,9r,12r)-4,5,12-tris(acetyloxy)-6-[(benzoyloxy)methyl]-2,10,10-trimethyl-11-oxatricyclo[7.2.1.0¹,⁶]dodecan-7-yl benzoate
(1s,2r,4s,5r,6r,7s,9r,12r)-4,5,12-tris(acetyloxy)-6-[(benzoyloxy)methyl]-2,10,10-trimethyl-11-oxatricyclo[7.2.1.0¹,⁶]dodecan-7-yl benzoate
[9,16,21,22-tetrahydroxy-5-(hydroxymethyl)-13,20,25-trimethyl-4,24-dioxo-3,23-dioxanonacyclo[14.10.1.0²,⁶.0²,¹⁴.0⁸,¹³.0¹⁰,¹².0¹⁷,¹⁹.0²⁰,²⁷.0²²,²⁶]heptacosa-1(27),5,25-trien-9-yl]methyl 2-methylbut-2-enoate
[9,16,21,22-tetrahydroxy-5-(hydroxymethyl)-13,20,25-trimethyl-4,24-dioxo-3,23-dioxanonacyclo[14.10.1.0²,⁶.0²,¹⁴.0⁸,¹³.0¹⁰,¹².0¹⁷,¹⁹.0²⁰,²⁷.0²²,²⁶]heptacosa-1(27),5,25-trien-9-yl]methyl 2-methylbut-2-enoate
(2r,3r,4r,5r,6r)-5-hydroxy-2-(hydroxymethyl)-6-[2-(4-hydroxyphenyl)ethoxy]-4-{[(2s,3r,4r,5r,6s)-3,4,5-trihydroxy-6-methyloxan-2-yl]methoxy}oxan-3-yl (2e)-3-(4-hydroxy-3-methoxyphenyl)prop-2-enoate
(2r,3r,4r,5r,6r)-5-hydroxy-2-(hydroxymethyl)-6-[2-(4-hydroxyphenyl)ethoxy]-4-{[(2s,3r,4r,5r,6s)-3,4,5-trihydroxy-6-methyloxan-2-yl]methoxy}oxan-3-yl (2e)-3-(4-hydroxy-3-methoxyphenyl)prop-2-enoate
[(3ar,4r,5r,7ar)-4-[(1ar,2r,3r,3ar,4r,5r,6r,7as)-2,5-dihydroxy-3-(5-hydroxy-2-oxo-5h-furan-3-yl)-4-[(2-hydroxy-3-methylbutanoyl)oxy]-3a-methyl-7-methylidene-hexahydroindeno[1,7a-b]oxiren-6-yl]-4,7a-dimethyl-2-oxo-tetrahydrofuro[2,3-c]pyran-5-yl]acetic acid
[(3ar,4r,5r,7ar)-4-[(1ar,2r,3r,3ar,4r,5r,6r,7as)-2,5-dihydroxy-3-(5-hydroxy-2-oxo-5h-furan-3-yl)-4-[(2-hydroxy-3-methylbutanoyl)oxy]-3a-methyl-7-methylidene-hexahydroindeno[1,7a-b]oxiren-6-yl]-4,7a-dimethyl-2-oxo-tetrahydrofuro[2,3-c]pyran-5-yl]acetic acid
n-{4-[n-(3-{[(2,3-dihydroxyphenyl)(hydroxy)methylidene]amino}propyl)-1-[2-(2,3-dihydroxyphenyl)-4,5-dihydro-1,3-oxazol-4-yl]formamido]butyl}-2-hydroxy-3-methoxybenzenecarboximidic acid
n-{4-[n-(3-{[(2,3-dihydroxyphenyl)(hydroxy)methylidene]amino}propyl)-1-[2-(2,3-dihydroxyphenyl)-4,5-dihydro-1,3-oxazol-4-yl]formamido]butyl}-2-hydroxy-3-methoxybenzenecarboximidic acid
n-{4-[n-(3-{[(2,3-dihydroxyphenyl)(hydroxy)methylidene]amino}propyl)-1-[(4s)-2-(2,3-dihydroxyphenyl)-4,5-dihydro-1,3-oxazol-4-yl]formamido]butyl}-2-hydroxy-3-methoxybenzenecarboximidic acid
n-{4-[n-(3-{[(2,3-dihydroxyphenyl)(hydroxy)methylidene]amino}propyl)-1-[(4s)-2-(2,3-dihydroxyphenyl)-4,5-dihydro-1,3-oxazol-4-yl]formamido]butyl}-2-hydroxy-3-methoxybenzenecarboximidic acid
4-methoxy-3-[4-({4-[(6-methoxy-2-methyl-1-oxo-3,4-dihydroisoquinolin-7-yl)oxy]-6-methyl-2h,5h,7h,8h-[1,3]dioxolo[4,5-g]isoquinolin-5-yl}methyl)phenoxy]benzaldehyde
4-methoxy-3-[4-({4-[(6-methoxy-2-methyl-1-oxo-3,4-dihydroisoquinolin-7-yl)oxy]-6-methyl-2h,5h,7h,8h-[1,3]dioxolo[4,5-g]isoquinolin-5-yl}methyl)phenoxy]benzaldehyde
(1s,2s,3s,4r,5r,6r,7s,9r,12r)-4,12-bis(acetyloxy)-2,3-dihydroxy-2,6,10,10-tetramethyl-7-{[(2e)-3-phenylprop-2-enoyl]oxy}-11-oxatricyclo[7.2.1.0¹,⁶]dodecan-5-yl benzoate
(1s,2s,3s,4r,5r,6r,7s,9r,12r)-4,12-bis(acetyloxy)-2,3-dihydroxy-2,6,10,10-tetramethyl-7-{[(2e)-3-phenylprop-2-enoyl]oxy}-11-oxatricyclo[7.2.1.0¹,⁶]dodecan-5-yl benzoate
n-{3-[n-(4-{[(2,3-dihydroxyphenyl)(hydroxy)methylidene]amino}butyl)-1-[(4s,5r)-2-(2,3-dihydroxyphenyl)-5-methyl-4,5-dihydro-1,3-oxazol-4-yl]formamido]propyl}-2,3-dihydroxybenzenecarboximidic acid
n-{3-[n-(4-{[(2,3-dihydroxyphenyl)(hydroxy)methylidene]amino}butyl)-1-[(4s,5r)-2-(2,3-dihydroxyphenyl)-5-methyl-4,5-dihydro-1,3-oxazol-4-yl]formamido]propyl}-2,3-dihydroxybenzenecarboximidic acid