Methyl Esters of Fatty Acids

Archive of Mass Spectra

 

The following mass spectra of methyl ester derivatives of fatty acids can be accessed directly from the tabulated links below. No comments or interpretation are provided here, as the general principles are discussed elsewhere. Further spectra will be added as they become available.

 

Methyl esters of saturated straight-chain fatty acids (including those labelled with stable isotopes)

Fatty acid >M+ Fatty acid M+
 
butyrate (4:0) 102    
pentanoate (5:0) 116 octadecanoate (18:0) 298
hexanoate (6:0) 130 nonadecanoate (19:0) 312
heptanoate (7:0) 144 eicosanoate (20:0) 326
octanoate (8:0) 158 heneicosanoate (21:0) 340
nonanoate (9:0) 172 docosanoate (22:0) 354
decanoate (10:0) 186 tricosanoate (23:0) 368
undecanoate (11:0) 200 tetracosanoate (24:0) 382
dodecanoate (12:0) 214 pentacosanoate (25:0) 396
tridecanoate (13:0) 228 hexacosanoate (26:0) 410
tetradecanoate (14:0) 242 heptacosanoate (27:0) 424
pentadecanoate (15:0) 256 octacosanoate (28:0) 438
hexadecanoate (16:0) 270 nonacosanoate (29:0) 452
heptadecanoate (17:0) 284 triacontanoate (30:0) 466
2,2-D-hexadecanoate (16:0) 272 1-13C-octadecanoate (18:0) 299
3,3-D-hexadecanoate (16:0) 272 2-13C-hexadecanoate (16:0) 271
4,4-D-hexadecanoate (16:0) 272    
D35-octadecanoate (18:0) 333    

Methyl esters of saturated branched-chain fatty acids

Fatty acid M+ Fatty acid M+
 
8-methyl-nonanoate (iso) 186 18-methyl-eicosanoate (anteiso) 340
8-methyl-decanoate (anteiso) 200    
10-methyl-undecanoate (iso) 214 20-methyl-heneicosanoate (iso) 354
10-methyl-dodecanoate (anteiso) 228 15-methyl-docosanoate 368
11-methyl-dodecanoate (iso) 228 20-methyl-docosanoate (anteiso) 368
12-methyl-tridecanoate (iso) 242 21-methyl-docosanoate (iso) 368
3-methyl-tetradecanoate 256 22-methyl-tricosanoate (iso) 382
9-methyl-tetradecanoate 256 17-methyl-tetracosanoate 396
12-methyl-tetradecanoate (anteiso) 256 18-methyl-tetracosanoate 396
13-methyl-tetradecanoate (iso) 256 22-methyl-tetracosanoate (anteiso) 396
3-methyl-pentadecanoate 270 23-methyl-tetracosanoate (iso) 396
14-methyl-pentadecanoate (iso) 270 24-methyl-pentacosanoate (iso) 410
3-methyl-hexadecanoate 284 20-methyl-hexacosanoate 424
10-methyl-hexadecanoate 284 21-methyl-hexacosanoate 424
14-methyl-hexadecanoate (anteiso) 284 24-methyl-hexacosanoate (anteiso) 424
15-methyl-hexadecanoate (iso) 284 26-methyl-heptacosanoate (iso) 438
16-methyl-heptadecanoate (iso) 298 26-methyl-octacosanoate (anteiso) 452
11-methyl-octadecanoate 312 28-methyl-nonacosanoate (iso) 466
16-methyl-octadecanoate (anteiso) 312 28-methyl-triacontanoate (anteiso) 480
17-methyl-octadecanoate (iso) 312 30-methyl-hentriacontanoate (iso) 494
18-methyl-nonadecanoate (iso) 326 30-methyl-dotriacontanoate (anteiso) 508
13-methyl-eicosanoate 340 32-methyl-tritriacontanoate (iso) 522
14-methyl-eicosanoate 340 32-methyl-tetratriacontanoate (anteiso) 536
4,8,12-trimethyl-tridecanoate 270 8,10-dimethyl-hexadecanoate 298
2,6,10,14-tetramethyl-pentadecanoate (pristanate) 312 3,7,11,15-tetramethyl-hexadecanoate (phytanate) 326

Methyl esters of monoenoic fatty acids (including dimethyl disulfide adducts)

Fatty acid M+ Fatty acid M+
 
9-dodecenoate (9-12:1) 212    
9-tetradecenoate (9-14:1) 240 5-eicosenoate (5-20:1) 324
3-trans-hexadecenoate 268 9-eicosenoate (9-20:1) 324
9-hexadecenoate (9-16:1) 268 11-eicosenoate (11-20:1) 324
11-hexadecenoate (11-16:1) 268 13-eicosenoate (13-20:1) 324
8-heptadecenoate (8-17:1) 282 11-docosenoate (11-22:1) 352
9-heptadecenoate (9-17:1) 282 13-docosenoate (13-22:1) 352
2-trans-octadecenoate (2-18:1) 296 15-tetracosenoate (15-24:1) 380
9-octadecenoate (9-18:1) 296 16-pentacosenoate (16-25:1) 394
11-octadecenoate (11-18:1) 296 17-hexacosenoate (17-26:1) 408
13-octadecenoate (13-18:1) 296 19-hexacosenoate (19-26:1) 408
    19-octacosenoate (19-28:1) 436
11-nonadecenoate (11-19:1) 310 21-triacontenoate (21-30:1) 464
15-methyl-hexadec-9-enoate 282 7-methyl-hexadec-6-enoate 282
3,7,11,15-tetramethylhexadec-trans-2-enoate (phytenate) 324    
9-octadecenoate (DMDS adduct) 390 11-octadecenoate (DMDS adduct) 390

Methyl esters of dienoic fatty acids (including MTAD adducts)

Fatty acid M+ Fatty acid M+
 
5,9-hexadecadienoate (5,9-16:2) 266 9,12-nonadecadienoate (9,12-19:2) 308
7,10-hexadecadienoate (16:2(n-6)) 266 8,11-eicosadienoate (20:2(n-9)) 322
9,12-hexadecadienoate (9,12-16:2) 266 11,14-eicosadienoate (20:2(n-6)) 322
5,9-heptadecadienoate (5,9-17:2) 280    
9,12-heptadecadienoate (9,12-17:2) 280 5,9-docosadienoate (5,9-22:2) 350
    5,13-docosadienoate (5,13-22:2) 350
4,7-octadecadienoate (4,7-18:2) 294 13,16-docosadienoate (22:2(n-6)) 350
6,9-octadecadienoate (6,9-18:2) 294    
9,12-octadecadienoate (18:2(n-6)) 294 5,9-tricosadienoate (5,9-23:2) 364
11,14-octadecadienoate (11,14-18:2)) 294 5,9-tetracosadienoate (5,9-24:2) 378
12,15-octadecadienoate (12,15-18:2)) 294 15,18-tetracosadienoate (24:2(n-6)) 378
3,9-octadecadienoate (3,9-18:2) 294    
5,9-octadecadienoate (5,9-18:2) 294    
5,12-octadecadienoate (5,12-18:2) 294 5,9-pentacosadienoate (5,9-25:2) 392
6,10-octadecadienoate (6,10-18:2) 294    
6,11-octadecadienoate (6,11-18:2) 294 5,9-hexacosadienoate (5,9-26:2) 406
7,12-octadecadienoate (7,12-18:2) 294 5,9-heptacosadienoate (5,9-27:2) 420
9,11-octadecadienoate (9,11-18:2) 294 5,9-octacosadienoate (5,9-28:2) 434
10,12-octadecadienoate (10,12-18:2) 294    
23-methyl-tetracos-5,9-dienoate 392 24-methyl-hexacosa-5,9-dienoate 420
25-methyl-hexacosa-5,9-dienoate 420 22-methyl-octacos-5,9-dienoate 448
9,11-octadecadienoate - MTAD adduct 407 12,14-octadecadienoate - MTAD adduct 407
10,12-octadecadienoate - MTAD adduct 407 13,15-octadecadienoate - MTAD adduct 407
11,13-octadecadienoate - MTAD adduct 407    

Methyl esters of trienoic acids including (MTAD adducts)

Fatty acid M+ Fatty acid M+
 
4,7,10-hexadecatrienoate (4,7,10-16:3) 264 5,8,11-eicosatrienoate (20:3(n-9)) 320
6,9,12-hexadecatrienoate (6,9,12-16:3) 264 5,11,14-eicosatrienoate (5,11,14-20:3) 320
7,10,13-hexadecatrienoate (16:3(n-3)) 264 7,11,14-eicosatrienoate (7,11,14-20:3) 320
9,12,15-hexadecatrienoate (16:3(n-1)) 264 7,13,17-eicosatrienoate (7,13,17-20:3) 320
    8,11,14-eicosatrienoate (20:3(n-6)) 320
8,11,14-heptadecatrienoate (17:3(n-3)) 278 10,13,16-eicosatrienoate (20:3(n-4)) 320
    11,14,17-eicosatrienoate (20:3(n-3)) 320
3,9,12-octadecatrienoate (3,9,12-18:3) 292 10,13,16-docosatrienoate (22:3(n-6)) 348
5,9,12-octadecatrienoate (5,9,12-18:3) 292 5,9,17-tetracosatrienoate (5,9,17-24:3) 376
6,8,12-octadecatrienoate (6,8,12-18:3) 292    
6,9,12-octadecatrienoate (18:3(n-6)) 292 5,9,19-hexacosatrienoate (5,9,19-26:3) 404
8,11,14-octadecatrienoate (18:3(n-4)) 292 5,9,19-octacosatrienoate (5,9,19-28:3) 432
9,12,15-octadecatrienoate (18:3(n-3)) 292    
11,14,17-octadecatrienoate (18:3(n-1)) 292 5,9,21-octacosatrienoate (5,9,21-28:3) 432
6,9,11-octadecatrienoate (6,9,11-18:3) 292 5,9,22-nonacosatrienoate (5,9,22-29:3) 446
8t,10t,12c-octadecatrienoate (8,10,12-18:3) 292 5,9,23-triacontatrienoate (5,9,23-30:3) 480
9c,11t,13t-octadecatrienoate (9,11,13-18:3) 292    
9c,11t,13c-octadecatrienoate (9,11,13-18:3) 292    
9c,11t,15c-octadecatrienoate (9,11,15-18:3) 292    
6,9,11-octadecatrienoate - MTAD adduct 405    
9,11,13-octadecatrienoate - MTAD adduct 1 405 9,11,13-octadecatrienoate - MTAD adduct 2 405

Methyl esters of tetra-, penta- and hexaenoic fatty acids

Fatty acid M+ Fatty acid M+
 
4,7,10,13-hexadecatetraenoate (16:4(n-3)) 262 5,8,11,14-eicosatetraenoate (20:4(n-6)) 318
6,9,12,15-hexadecatetraenoate (16:4(n-1)) 262 5,11,14,17-eicosatetraenoate (5,11,14,17-20:4) 318
5,8,11,14-octadecatetraenoate (18:4(n-4)) 290 8,11,14,17-eicosatetraenoate (20:4(n-3)) 318
5,9,12,15-octadecatetraenoate 290 10,13,16,19-eicosatetraenoate or 20:4(n-1) 318
6,9,11,15-octadecatetraenoate 290    
6,9,12,15-octadecatetraenoate (18:4(n-3)) 290 7,10,13,16-docosatetraenoate (22:4(n-6)) 346
8,11,14,17-octadecatetraenoate (18:4(n-1)) 290 10,13,16,19-docosatetraenoate or 22:4(n-3) 346
9c,11t,13t,15c-octadecatetraenoate (9,11,13,15-18:4) 290 9,12,15,18-tetracosatetraenoate (24:4(n-6)) 374
6,9,11,15-octadecatetraenoate - MTAD adduct 403 5,8,11,13-eicosatetraenoate - MTAD adduct 431
3,6,9,12,15-octadecapentaenoate (18:5(n-3)) 288 5,8,11,14,17-octadecapentaenoate (18:5(n-1)) 288
5,8,11,14,17-eicosapentaenoate (20:5(n-3)) 316 4,7,10,13,16-docosapentaenoate (22:5(n-6)) 344
6,9,12,15,18-heneicosapentaenoate (21:5(n-3)) 330 7,10,13,16,19-docosapentaenoate (22:5(n-3)) 344
4,7,10,13,16,19-docosahexaenoate (22:6(n-3)) 342 6,9,12,15,18,21-tetracosahexaenoate (24:6(n-3)) 370

Methyl esters of allenic and acetylenic fatty acids

Fatty acid M+ Fatty acid M+
3,4-tetradecadienoate (3,4-14:2) 238 7,8-octadecadienoate (7,8-18:2) 294
4,5-tetradecadienoate (4,5-14:2) 238 8,9-octadecadienoate (8,9-18:2) 294
10,11-tetradecadienoate (10,11-14:2) 238 9,10-octadecadienoate (9,10-18:2) 294
11,12-tetradecadienoate (11,12-14:2) 238 10,11-octadecadienoate (10,11-18:2) 294
12,13-tetradecadienoate (12,13-14:2) 238 11,12-octadecadienoate (11,12-18:2) 294
5,6-octadecadienoate (5,6-18:2) 294 12,13-octadecadienoate (12,13-18:2) 294
6,7-octadecadienoate (6,7-18:2) 294 13,14-octadecadienoate (13,14-18:2) 294
octadec-6-ynoate 294 octadeca-9-yn,trans-11-enoate 292
octadec-9-ynoate 294 octadeca-9-en,12-ynoate 292
5,7-nonadiynoate 164 eicocosa-11-en,14-ynoate 320
2,4-tridecadiynoate 220 eicos-11-yn,trans-13-enoate 320
3,5-tetradecadiynoate 234 docos-13-yn,trans-15-enoate 348
4,6-tetradecadiynoate 234 tetracos-15-yn,trans-17-enoate 376
5,7-hexadecadiynoate 262 hexacos-17-yn,trans-19-enoate 404
10,12-heptadecadiynoate 276    
6,8-octadecadiynoate 290 octadeca-6,9-dien-12-ynoate 290
7,9-octadecadiynoate 290 octadeca-8,10-dien-12-ynoate 290
8,10-octadecadiynoate 290 octadeca-9-yn,11-trans,13-cis/trans-dienoate 290
9,11-octadecadiynoate 290 eicocosa-8,11-dien-14-ynoate 318
10,12-octadecadiynoate 290    

Methyl esters of natural cyclic fatty acids

Fatty acid M+ Fatty acid M+
 
9,10-methylene-hexadecanoate 282 11,12-methylene-octadecanoate 310
9,10-methylene-octadecanoate 310 11,12-methylene-eicosanoate 338
8,9-methylene-heptadec-8-enoate 294 9,10-methylene-octadec-9-enoate 308
11-cyclopentylundecanoate 268 13-cyclopentyltridecanoate 296
11-cyclopent-2-enyl-undecanoate 266 13-cyclopent-2-enyl-tridec-4-enoate-dmds 480
13-cyclopent-2-enyl-tridecanoate 294 13-cyclopent-2-enyl-tridec-6-enoate-dmds 480
13-cyclopent-2-enyl-tridec-6-enoate 292    
11-cyclohexyl-undecanoate 282    
11-phenyl-undecanoate 276 13-phenyl-tridecanoate 304
13-phenyl-tridec-9-enoate 302 15-phenyl-pentadec-9-enoate 330
    coumarate - TMS ether 250
ferulate 208 ferulate - TMS ether 280
sinapate - acetate 280 sinapate - TMS ether 310
    cafeate - TMS ether 338

Methyl esters of epoxy, furanoid and oxo fatty acids

Fatty acid M+ Fatty acid M+
 
9,10-epoxyoctadecanoate 312 12,13-epoxyoctadec-9-enoate 310
9,10-epoxyoctadec-12-enoate 310 9,10-epoxy,18-hydroxy-octadecanoate - TMS 400
8-(5-hexyl-2-furyl)-octanoate 308    
10,13-epoxy-11,12-dimethyl-hexadecadienoate 308 12,15-epoxy-13,14-dimethyl-octadecadienoate 336
11,14-epoxy-12,13-dimethyl-hexadecadienoate 308 12,15-epoxy-13-methyl-eicosadienoate 350
10,13-epoxy-11-methyl-octadecadienoate 322 12,15-epoxy-13,14-dimethyl-eicosadienoate 364
10,13-epoxy-11,12-dimethyl-octadecadienoate 336 14,17-epoxy-15,16-dimethyl-eicosadienoate 364
5-oxo-octadecanoate 312 12-oxo-octadecanoate 312
7-oxo-octadecanoate 312 9,10-dideutero-12-oxo-octadecanoate 314
    12-oxo-octadec-9-enoate 310
5-oxo-octadecanoate - oxime 341 12-oxo-octadecanoate - oxime 341
7-oxo-octadecanoate - oxime 341    

Methyl esters of hydroxy fatty acids

Fatty acid M+ Fatty acid M+
 
3-hydroxy-octanoate 174 2-hydroxy-heptadecanoate 300
2-hydroxy-decanoate 202 2-hydroxy-octadecanoate 314
3-hydroxy-decanoate 202 10-hydroxy-octadecanoate 314
2-hydroxy-dodecanoate 230 12-hydroxy-octadecanoate 314
3-hydroxy-dodecanoate 230 17-hydroxy-octadecanoate 314
12-hydroxy-dodecanoate 230 18-hydroxy-octadecanoate 314
2-hydroxy-tetradecanoate 258 9-hydroxy-nonadecanoate 328
3-hydroxy-tetradecanoate 258 2-hydroxy-eicosanoate 342
6-hydroxy-tetradecanoate 258 20-hydroxy-eicosanoate 342
13-hydroxy-tetradecanoate 258 2-hydroxy-docosanoate 370
2-hydroxy-pentadecanoate 272 22-hydroxy-docosanoate 370
15-hydroxy-pentadecanoate 272 2-hydroxy-tricosanoate 384
2-hydroxy-hexadecanoate 286 2-hydroxy-tetracosanoate 398
3-hydroxy-hexadecanoate 286 24-hydroxy-tetracosanoate 398
8-hydroxy-hexadecanoate 286 2-hydroxy-pentacosanoate 412
15-hydroxy-hexadecanoate 286 2-hydroxy-hexacosanoate 426
16-hydroxy-hexadecanoate 286 26-hydroxy-hexacosanoate 426
2-hydroxy-16-methyl-heptadecanoate 314    
9-hydroxy-octadec-12-enoate 312 2-hydroxy-tetracos-17-enoate 396
12-hydroxy-octadec-9-enoate 312 2-hydroxy-pentacos-16-enoate 410
18-hydroxy-octadec-9-enoate 312 2-hydroxy-pentacos-18-enoate 410
14-hydroxy-eicos-11-enoate 340 2-hydroxy-hexacos-17-enoate 424
20-hydroxy-eicos-11-enoate 340 2-hydroxy-hexacos-19-enoate 424
22-hydroxy-docos-13-enoate 368 2-hydroxy-heptacos-18-enoate 438
2-hydroxy-tetracos-15-enoate 396    
9-hydroxy-octadec-10,12-dienoate 310 15-hydroxy-octadec-9,12-dienoate 310
2-hydroxy-octadeca-9,12,15-trienoate 308    
3-hydroxy-decanoate - TMS 274 15-hydroxy-octadecanoate - TMS 386
3-hydroxy-dodecanoate - TMS 302 17-hydroxy-octadecanoate - TMS 386
2-hydroxy-tetradecanoate - TMS 330 18-hydroxy-octadecanoate - TMS 386
3-hydroxy-tetradecanoate - TMS 330 9-hydroxy-nonadecanoate - TMS 400
15-hydroxy-pentadecanoate - TMS 344 11-hydroxy-nonadecanoate - TMS 400
2-hydroxy-hexadecanoate - TMS 358 20-hydroxy-eicosanoate - TMS 414
11-hydroxy-hexadecanoate - TMS 358 21-hydroxy-heneicosanoate - TMS 428
13-hydroxy-hexadecanoate - TMS 358 2-hydroxy-docosanoate - TMS 442
14-hydroxy-hexadecanoate - TMS 358 22-hydroxy-docosanoate - TMS 442
15-hydroxy-hexadecanoate - TMS 358 2-hydroxy-tricosanoate - TMS 456
16-hydroxy-hexadecanoate - TMS 358 23-hydroxy-tricosanoate - TMS 456
9-hydroxy-heptadecanoate - TMS 372 2-hydroxy-tetracosanoate - TMS 470
17-hydroxyheptadecanoate - TMS 372 24-hydroxy-tetracosanoate - TMS 470
2-hydroxy-octadecanoate - TMS 386 2-hydroxy-pentacosanoate - TMS 484
10-hydroxy-octadecanoate - TMS 386 2-hydroxy-hexacosanoate - TMS 498
13-hydroxy-octadecanoate - TMS 386 26-hydroxy-hexacosanoate - TMS 498
9-hydroxy-octadec-12-enoate - TMS 384 22-hydroxy-docos-13-enoate - TMS 440
12-hydroxy-octadec-9-enoate - TMS 384 2-hydroxy-tetracos-15-enoate - TMS 468
18-hydroxy-octadec-9-enoate - TMS 384 2-hydroxy-pentacos-16-enoate - TMS 482
14-hydroxy-eicos-11-enoate - TMS 412 2-hydroxy-pentacos-18-enoate - TMS 482
20-hydroxy-eicos-11-enoate - TMS 412 2-hydroxy-hexacos-19-enoate - TMS 496
9-hydroxy-octadeca-10,12-dienoate - TMS 382 15-hydroxy-octadeca-9,12-dienoate - TMS 382
9,10,18-trihydroxy-octadecanoate - TMS 562 9,10,18-trihydroxy-octadec-12-enoate - TMS 560
9,10-dihydroxyhexadecanoate - TMS 446 9,10-dihydroxy-1,18-octadecanedioate - TMS 516
9,10-dihydroxy-1,18-octadecanedioate 374 9,10-dihydroxy-1,20-eicosanedioate - TMS 546
15-hydroxy-pentadecanoate - acetate 314 18-hydroxy-octadec-9,12-dienoate - acetate 352
2-hydroxy-hexadecanoate - acetate 328    
18-hydroxy-octadec-9-enoate - acetate 354 10,16-dihydroxy-hexadecanoate - acetate 386

Methyl esters of methoxy fatty acids

Fatty acid M+ Fatty acid M+
 
12-methoxy-octadec-9-enoate 326    

Methyl esters of di- and tricarboxylic fatty acids

Fatty acid M+ Fatty acid M+
 
1,5-pentanedioate 160 1,12-dodecanedioate 258
1,6-hexanedioate 174 1,14-tetradecanedioate 286
1,7-heptanedioate 188 1,16-hexadecanedioate 314
1,8-octanedioate 202 1,18-octadecanedioate 342
1,9-nonanedioate 216 1,20-eicosanedioate 370
1,10-decanedioate 230 1,22-docosanedioate 398
1,11-undecanedioate 244 1,23-tricosanedioate 412
2-methyl-1,21-heneicosanedioate 398 2-methyl-1,23-tricosanedioate 426
1,18-octadec-9-enedioate 340 1,20-eicos-9-enedioate 368
1,18-octadec-6,9-dienedioate 338    
1,4,12-dodecanetrioate 302 1,4,14-tetradecanetrioate 330

Methyl esters of halogenated fatty acids

Fatty acid M+ Fatty acid M+
 
2-fluoro-octadecanoate 316 18-fluoro-octadec-9-enoate 314
18-fluoro-octadecanoate 316 2,2-difluoro-octadecanoate 334
2-bromo-hexadecanoate 350    

Methyl esters of thia fatty acids

Fatty acid M+ Fatty acid M+
 
6-thia-laurate 232 9-thia-stearate 316
    10-thia-stearate 316
2-thia-stearate 316 11-thia-stearate 316
3-thia-stearate 316 12-thia-stearate 316
4-thia-stearate 316 13-thia-stearate 316
5-thia-stearate 316 14-thia-stearate 316
6-thia-stearate 316 15-thia-stearate 316
7-thia-stearate 316 16-thia-stearate 316
8-thia-stearate 316 17-thia-stearate 316
6,7-dithia-stearate 334 10,15-dithia-stearate 334
6,8-dithia-stearate 334 11,15-dithia-stearate 334
6,9-dithia-stearate 334 12,15-dithia-stearate 334
6,10-dithia-stearate 334 13,15-dithia-stearate 334
6,11-dithia-stearate 334 14,15-dithia-stearate 334

Methyl esters of oxylipins

Fatty acid M+ Fatty acid M+
12-oxophytodienoate 306    

Updated September 5, 2013