20194-45-0Relevant academic research and scientific papers
Identification and total synthesis of novel fatty acids from the siphonarid limpet Siphonaria denticulata
Carballeira,Cruz,Hill,De Voss,Garson
, p. 1426 - 1429 (2001)
The novel fatty acids 17-methyl-6(Z)-octadecenoic acid and 17-methyl-7(Z)-octadecenoic acid were identified for the first time in nature in the mollusk Siphonaria denticulata from Queensland, Australia. The principal fatty acids in the limpet were hexadecanoic acid, octadecanoic acid, and (Z)-9-octadecenoic acid, while the most interesting series of monounsaturated fatty acids was a family of five nonadecenoic acids with double bonds at either Δ7, Δ9, Δ12, or Δ13. The novel compounds were characterized using a combination of GC-MS and chemical transformations, such as dimethyl disulfide derivatization. The first total syntheses for the two novel methyl-branched nonadecenoic acids are also described, and these were accomplished in four to five steps and in high yields.
A general route to N'-(2,2-difluoro-3-hydroxyalkanoyl)nornicotines
Fukuda, Hiroshi,Kitazume, Tomoya
, p. 171 - 176 (1995)
The preparation of a variety of N'-(2,2-difluoro-3-hydroxyalkanoyl)nornicotines via a Reformatsky-type reaction of ethyl bromodifluoroacetate with aldehydes is described.The difluoromethylene unit may be regarded as an isopolar and isosteric replacement f
Structural and Functional Analysis of Bacterial Sulfonosphingolipids and Rosette-Inducing Factor 2 (RIF-2) by Mass Spectrometry-Guided Isolation and Total Synthesis
Beemelmanns, Christine,Jautzus, Theresa,King, Nicole,Leichnitz, Daniel,Peng, Chia-Chi,Ragu?, Luka,Regestein, Lars,Rutaganira, Florentine U. N.
supporting information, (2022/01/04)
We have analyzed the abundance of bacterial sulfonosphingolipids, including rosette-inducing factors (RIFs), in seven bacterial prey strains by using high-resolution tandem mass spectrometry (HRMS2) and molecular networking (MN) within the Glob
Stereoselective synthesis of unnatural (2S, 3S)-6-hydroxy-4-sphingenine-containing sphingolipids
Leichnitz, Daniel,Pflanze, Sebastian,Beemelmanns, Christine
supporting information, p. 6964 - 6969 (2019/08/01)
6-Hydroxy-(4E)-sphingenine-containing sphingolipids are found in mammalian and bacterial membranes and have multiple intra- and intercellular functions. Most sphingolipids contain a (2S,3R)-2-amino-1,3-diol core structure, but only limited examples of unnatural (2S,3S)-2-amino-1,3-diol derivates have so far been reported. Using an underexplored hydrozirconation-transmetalation reaction and an unusual three-step-one-pot deprotection sequence, we were able to synthesize several unnatural (2S,3S)-6-hydroxy-(4E)-sphingenine-containing sphingolipids in only three (protected) or four (deprotected) consecutive steps, respectively, including a fluoresence-labeled derivative suitable for future biological studies.
An asymmetric synthesis of sulfobacin A
Sharma, Anubha,Gamre, Sunita,Chattopadhyay, Subrata
, p. 3705 - 3707 (2008/02/09)
A facile synthesis of sulfobacin A has been developed starting from (R)-cyclohexylideneglyceraldehyde (11). The key steps in the synthesis are the highly diastereocontrolled allylation of 11 and syn-selective reduction of a ketone derived from 11. The oth
Influence of terminal branching on the transdermal permeation-enhancing activity in fatty alcohols and acids
Klimentova, Jana,Kosak, Petr,Vavrova, Katerina,Holas, Tomas,Hrabalek, Alexandr
, p. 7681 - 7687 (2007/10/03)
In order to investigate the effect of terminal chain branching in the skin permeation enhancers, seven alcohols and seven acids with the chain length of 8-12 carbons and terminal methyl or ethyl branching were prepared. Their transdermal permeation-enhancing activities were evaluated in vitro using theophylline as a model permeant and porcine skin, and compared to those of the linear standards. Terminal methyl branching increased the enhancing activity only in 12C acid, no effect was seen in the shorter ones. Terminal ethyl however produced a significant increase in activity. In the alcohols, the branching was likely to change the mode of action, due to a different relationship between the activity and the chain length.
Synthesis of racemic lipid unit of the nucleoside antibiotic, liposidomycin-B
Kalyanakumar,Chadha,Chattopadhyay,Mamdapur
, p. 356 - 358 (2007/10/03)
The lipid part (10) of liposidomycin-B has been synthesised through functional manipulation of undecenoic acid (1) which involves chain extension via Reformatsky reaction and introduction of the methyl branching through organocuprate coupling.
Total Synthesis of (2S,3S,4R)-2--16-methylheptadecane-1,3,4-triol 3,4-dibenzoate, a Partially Protected Ceramide Part of Sponge Cerebrosides
Nakashima, Hideki,Hirata, Norihiko,Iwamura, Takeru,Yamagiwa, Yoshiro,Kamikawa, Tadao
, p. 2849 - 2858 (2007/10/02)
(2S,3S,4R)-2--16-methylheptadecane-1,3,4-triol 3,4-dibenzoate 32, apertially protected ceramide part of a cerebroside from the marine sponge Halichondria japonica, has been synthesized from L-ascorbic acid, and its absolute stereochemistry has been determined.The key steps in the synthesis include the regioselective ring opening of chiral epoxide 5 with a 2-alkyl-2-lithio-1,3-dithiane and the introduction of a hydroxymethylene synthon using Dondoni's protocol to assemble C(1) and C(2) functionality.
CONVENIENT SYNTHESES OF SIX TUNICAMYCIN ACIDS
Grzeszczyk, B.,Konowal, A.,Zamojski, A.
, p. 1627 - 1632 (2007/10/02)
10-Methylundecanol (15), obtained in five steps from sebacic acid, served as substrate for the synthesis of the ester 3-Et, via oxidation to aldehyde and Wittig condensation with stabilized ylid.From 3-Et next ester, 2-Et, was obtained by hydrogenation.Reduction of the ester grouping in 2-Et to the alcohol, followed by oxidation to aldehyde provided a substrate for another Wittig condensation leading to 8-Me.On the other hand, bromide 17, obtained from 15, was used for alkylation of propargylic alcohol.The product obtained, 18, served for the synthesis of acids 5 and 6.Ester 10-Et was obtained from 18 via hydrogenation of the triple bond, oxidation to aldehyde and condensation with a stabilized Wittig ylid.The yields of all steps were good to excellent. Key words: higher fatty acids, tunicamycin acids.
Synthesis of 14-methylpentadecan-3-one and 2-methylheptadecane
Kad, G. L.,Gupta, Sangita
, p. 581 - 583 (2007/10/02)
Li2CuCl4 catalysed coupling of 1-tetrahydropyranyloxy-8-octanylmagnesium bromide (III) with isobutyl bromide yields IV which on depyranylation with PPTS/MeOH followed by treatment with PBr3 affords the key intermediate 1-bromo-10-methylundecane (VI).Regioselective alkylation of α-lithio-2-butanone N,N-dimethylhydrazone with VI in THF at -78 deg C followed by oxidative hydrolysis with aq.NaIO4 at pH 7 results in the formation of 14-methylpentadecan-3-one (I).Coupling of VI with hexylmagnesium bromide using Li2CuCl4 as catalyst furnishes the target compound (II).
