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Search for "MMPP" in Full Text gives 6 result(s) in Beilstein Journal of Organic Chemistry.
Synthesis of ether lipids: natural compounds and analogues
- Marco Antônio G. B. Gomes,
- Alicia Bauduin,
- Chloé Le Roux,
- Romain Fouinneteau,
- Wilfried Berthe,
- Mathieu Berchel,
- Hélène Couthon and
- Paul-Alain Jaffrès
Beilstein J. Org. Chem. 2023, 19, 1299–1369, doi:10.3762/bjoc.19.96
Graphical Abstract
Figure 1: Chemical structure of some natural ether lipids (ELs).
Figure 2: Synthesis of lyso-PAF and PAF from 1-O-alkylglycerol [64].
Figure 3: Synthesis of lyso-PAF from 1,3-benzylideneglycerol 3.1 [69].
Figure 4: A) Synthesis of the two enantiomers of octadecylglycerol (4.6 and 4.10) from ᴅ-mannitol (4.1); B) s...
Figure 5: Four-step synthesis of PAF 5.6 from (S)-glycidol [73].
Figure 6: Synthesis of 1-O-alkylglycerol A) from solketal, B) from ᴅ- or ʟ-tartaric acid and the intermediate ...
Figure 7: Synthesis of EL building blocks starting from substituted glycidol 7.1a–c [82].
Figure 8: Synthesis of PAF 8.5 by using phosphoramidite 8.2 [86].
Figure 9: Synthesis of oleyl-PAF 9.7 from ʟ-serine [88].
Figure 10: Synthesis of racemic analogues of lyso-PAF 10.8 and PAF 10.9 featuring a phenyl group between the g...
Figure 11: Synthesis of racemic deoxy-lyso-PAF 11.7 and deoxy-PAF 11.8 [91].
Figure 12: Synthesis of racemic thio-PAF 12.8 [93].
Figure 13: Racemic synthesis of 13.6 to illustrate the modification of the glycerol backbone by adding a methy...
Figure 14: Racemic synthesis of 14.5 as an illustration of the introduction of methyl substituents on the glyc...
Figure 15: Synthesis of functionalized sn-2-acyl chains of PC-EL; A) Steglich esterification or acylation reac...
Figure 16: Synthesis of racemic mc-PAF (16.3), a carbamate analogue of PAF [102].
Figure 17: A) Synthesis of (R)-17.2 and (S)-17.6 starting from (S)-solketal (17.1); B) synthesis of N3-PAF (17...
Figure 18: Modification of the phosphocholine polar head to produce PAF analogues [81].
Figure 19: Racemic PAF analogues 19.3 and 19.5 characterized by the absence of the phosphate group [107].
Figure 20: Synthesis of PIP3-PAF (20.7) [108].
Figure 21: Large-scale synthesis of C18-edelfosine (21.8) [116].
Figure 22: Synthesis of C16-edelfosine (22.10) starting from isopropylidene-ʟ-glyceric acid methyl ester (22.1...
Figure 23: Phosphocholine moiety installation by the use of chlorophosphite 23.2 as key reagent [119].
Figure 24: Synthesis of rac-1-alkyl-2-O-methylglycerol (AMG) [120].
Figure 25: Synthesis of stereocontrolled 1-alkyl-2-O-methyl glycerol 25.9 (AMG) from dimethyl ᴅ-tartrate [81].
Figure 26: A) Racemic synthesis of thioether 26.4 [129,130], B) structure of sulfone analogue 26.5 [129].
Figure 27: Stereocontrolled synthesis of C18-edelfosine thioether analogue 27.8 [118].
Figure 28: Synthesis of thioether 28.4 that include a thiophosphate function [134].
Figure 29: Synthesis of ammonium thioether 29.4 and 29.6 [135].
Figure 30: Synthesis of the N-methylamino analogue of edelfosine 30.6 (BN52211) [138].
Figure 31: Synthesis of 1-desoxy analogues of edelfosine; A) with a saturated alkyl chain; B) synthesis of the...
Figure 32: Stereocontrolled synthesis of edelfosine analogue (S)-32.8 featuring a C18:1 lipid chain [142].
Figure 33: Synthesis of edelfosine analogues with modulation of the lipid chain; A) illustration with the synt...
Figure 34: Synthesis of phospholipid featuring a carbamate function to link the lipid chain to the glycerol un...
Figure 35: Synthesis of sesquiterpene conjugates of phospho glycero ether lipids [148].
Figure 36: Racemic synthesis of methyl-substituted glycerol analogues 36.7 and 36.10: A) synthesis of diether ...
Figure 37: Racemic synthesis of ilmofosine (37.6) [155,156].
Figure 38: A) Stereoselective synthesis of 38.5 via a stereoselective hydroboration reaction; B) synthesis of ...
Figure 39: Racemic synthesis of SRI62-834 (39.6) featuring a spiro-tetrahydrofurane heterocycle in position 2 ...
Figure 40: Racemic synthesis of edelfosine analogue 40.5 featuring an imidazole moiety in sn-2 position [160].
Figure 41: Racemic synthesis of fluorine-functionalized EL: A) Synthesis of 41.6 and B) synthesis of 41.8 [161-163].
Figure 42: A) Synthesis of the β-keto-ester 42.6 that also features a decyl linker between the phosphate and t...
Figure 43: Synthesis of phosphonate-based ether lipids; A) edelfosine phosphonate analogue 43.7 and B) thioeth...
Figure 44: Enantioselective synthesis of phosphonates 44.3 and 44.4 [171].
Figure 45: Racemic synthesis of phosphinate-based ether lipid 45.10 [172].
Figure 46: Racemic synthesis of edelfosine arsonium analogue 46.5 [173].
Figure 47: Synthesis of edelfosine dimethylammonium analogue 47.2 [118].
Figure 48: Synthesis of rac-C18-edelfosine methylammonium analogue 48.4 [176].
Figure 49: A) Synthesis of edelfosine N-methylpyrrolidinium analogue 49.2 or N-methylmorpholinium analogue 49.3...
Figure 50: A) Synthesis of edelfosine’s analogue 50.4 with a PE polar group; B) illustration of a pyridinium d...
Figure 51: A) Synthesis of 51.4 featuring a thiazolium cationic moiety; B) synthesis of thiazolium-based EL 51...
Figure 52: Synthesis of cationic ether lipids 52.3, 52.4 and 52.6 [135,183].
Figure 53: Synthesis of cationic carbamate ether lipid 53.5 [184].
Figure 54: Synthesis of cationic sulfonamide 54.5 [185].
Figure 55: Chemical structure of ONO-6240 (55.1) and SRI-63-119 (55.2).
Figure 56: Synthesis of non-ionic ether lipids 56.2–56.9 [188].
Figure 57: Synthesis of ether lipid conjugated to foscarnet 57.6 [189].
Figure 58: A) Synthesis of ether lipid conjugated to arabinofuranosylcytosine; B) synthesis of AZT conjugated ...
Figure 59: Synthesis of quercetin conjugate to edelfosine [191].
Figure 60: Synthesis of 60.8 (Glc-PAF) [194].
Figure 61: A) Synthesis of amino ether lipid 61.7 functionalized with a rhamnose unit and its amide analogue 6...
Figure 62: A) Synthesis of glucose ether lipid 62.4; B) structure of ether lipid 62.5 possessing a maltose uni...
Figure 63: A) Synthesis of glucuronic methyl ester 63.8; B) structure of cellobiose 63.9 and maltose 63.10 ana...
Figure 64: A) Synthesis of maltosyl glycerolipid 64.7; B) structure of lactose analogue 64.8 prepared followin...
Figure 65: A) Asymmetric synthesis of the aglycone moiety starting from allyl 4-methoxyphenyl ether; B) glycos...
Figure 66: A) Synthesis of ohmline possessing a lactose moiety. B) Structure of other glyco glycero lipids pre...
Figure 67: A) Synthesis of lactose-glycerol ether lipid 67.5; B) analogues possessing a maltose (67.6) or meli...
Figure 68: Synthesis of digalactosyl EL 68.6, A) by using trityl, benzyl and acetyl protecting groups, B) by u...
Figure 69: A) Synthesis of α-ohmline; B) structure of disaccharide ether lipids prepared by using similar meth...
Figure 70: Synthesis of lactose ether lipid 70.3 and its analogue 70.6 featuring a carbamate function as linke...
Figure 71: Synthesis of rhamnopyranoside diether 71.4 [196].
Figure 72: Synthesis of 1-O-hexadecyl-2-O-methyl-3-S-(α-ᴅ-1'-thioglucopyranosyl)-sn-glycerol (72.5) [225].
Figure 73: A) Preparation of lipid intermediate 73.4; B) synthesis of 2-desoxy-C-glycoside 73.10 [226].
Figure 74: Synthesis of galactose-pyridinium salt 74.3 [228].
Figure 75: Synthesis of myo-inositol derivative Ino-C2-PAF (75.10) [230].
Figure 76: A) Synthesis of myo-inositol phosphate building block 76.7; B) synthesis of myo-inositolphosphate d...
Figure 77: A) Synthesis of phosphatidyl-3-desoxy-inositol 77.4; B) synthesis of phosphono-3-desoxyinositol 77.9...
Figure 78: A) Structure of diether phosphatidyl-myo-inositol-3,4-diphosphate 78.1; B) synthesis of phosphatidy...
Figure 79: A) Synthesis of diether-phosphatidyl derivative 79.4 featuring a hydroxymethyl group in place of a ...
Figure 80: Synthesis of Glc-amine-PAF [78].
Figure 81: Synthesis of glucosamine ether lipid 81.4 and its analogues functionalized in position 3 of the ami...
Figure 82: Synthesis of fully deprotected aminoglucoside ether lipid 82.5 [246].
Figure 83: Synthesis of C-aminoglycoside 83.12 using Ramberg–Bäcklund rearrangement as a key step [250].
Figure 84: A) List of the most important glyco lipids and amino glyco lipids included in the study of Arthur a...
Figure 85: Synthesis of mannosamine ether lipid 85.6 [254].
Figure 86: A) Synthesis of glucosamine ether lipids with a non-natural ʟ-glucosamine moiety; B) synthesis of e...
Figure 87: A) Structure of the most efficient anticancer agents 87.1–87.4 featuring a diamino glyco ether lipi...
Figure 88: A) Synthesis of diamino glyco ether lipid 87.4; B) synthesis of bis-glycosylated ether lipid 88.10 [256]....
Figure 89: Synthesis of triamino ether lipid 89.4 [260].
Figure 90: Synthesis of chlorambucil conjugate 90.7 [261].
Figure 91: Three main methods for the preparation of glycerol ether lipid 91.3; A) from solketal and via a tri...
Figure 92: Four different methods for the installation of the phosphocholine polar head group; A) method using...
Figure 93: Illustration of two methods for the installation of saccharides or aminosaccharides; A) O-glycosyla...
Enduracididine, a rare amino acid component of peptide antibiotics: Natural products and synthesis
- Darcy J. Atkinson,
- Briar J. Naysmith,
- Daniel P. Furkert and
- Margaret A. Brimble
Beilstein J. Org. Chem. 2016, 12, 2325–2342, doi:10.3762/bjoc.12.226
- mannopeptimycin gene clusters, three pairs of enzymes were found to have high sequence homology, mmpP/endP, mppR/endR and mmpQ/endQ [49][50]. MppP is a PLP-dependent hydroxylase and catalyses the conversion of L-arginine (18) and molecular oxygen to 2-oxo-4-hydroxy-5-guanidinovaleric acid (20, Scheme 1) [51]. The
Graphical Abstract
Figure 1: Structures of the enduracididine family of amino acids (1–6).
Figure 2: Enduracidin A (7) and B (8).
Figure 3: Minosaminomycin (9) and related antibiotic kasugamycin (10).
Figure 4: Enduracididine-containing compound 11 identified in a cytotoxic extract of Leptoclinides dubius [32].
Figure 5: Mannopeptimycins α–ε (12–16).
Figure 6: Regions of the mannopeptimycin structure investigated in structure–activity relationship investigat...
Figure 7: Teixobactin (17).
Scheme 1: Proposed biosynthesis of L-enduracididine (1) and L-β-hydroxyenduracididine (5).
Scheme 2: Synthesis of enduracididine (1) by Shiba et al.
Scheme 3: Synthesis of protected enduracididine diastereomers 31 and 32.
Scheme 4: Synthesis of the C-2 azido diastereomers 36 and 37.
Scheme 5: Synthesis of 2-azido-β-hydroxyenduracididine derivatives 38 and 39.
Scheme 6: Synthesis of protected β-hydroxyenduracididine derivatives 40 and 41.
Scheme 7: Synthesis of C-2 diastereomeric amino acids 46 and 47.
Scheme 8: Synthesis of protected β-hydroxyenduracididines 51 and 52.
Scheme 9: General transformation of alkenes to cyclic sulfonamide 54 via aziridine intermediate 53.
Scheme 10: Synthesis of (±)-enduracididine (1) and (±)-allo-enduracididine (3).
Scheme 11: Synthesis of L-allo-enduracididine (3).
Scheme 12: Synthesis of protected L-allo-enduracididine 63.
Scheme 13: Synthesis of β-hydroxyenduracididine derivative 69.
Scheme 14: Synthesis of minosaminomycin (9).
Scheme 15: Retrosynthetic analysis of mannopeptimycin aglycone (77).
Scheme 16: Synthesis of protected amino acids 87 and 88.
Scheme 17: Synthesis of mannopeptimycin aglycone (77).
Scheme 18: Synthesis of N-mannosylation model guanidine 92 and attempted synthesis of benzyl protected mannosy...
Scheme 19: Synthesis of benzyl protected mannosyl D-β-hydroxyenduracididine 97.
Scheme 20: Synthesis of L-β-hydroxyenduracididine 98.
Scheme 21: Total synthesis of mannopeptimycin α (12) and β (13).
Scheme 22: Synthesis of protected L-allo-enduracididine 102.
Scheme 23: The solid phase synthesis of teixobactin (17).
Scheme 24: Retrosynthesis of the macrocyclic core 109 of teixobactin (17).
Scheme 25: Synthesis of macrocycle 117.
Catalytic asymmetric synthesis of biologically important 3-hydroxyoxindoles: an update
- Bin Yu,
- Hui Xing,
- De-Quan Yu and
- Hong-Min Liu
Beilstein J. Org. Chem. 2016, 12, 1000–1039, doi:10.3762/bjoc.12.98
- yields (up to 99% yield, Scheme 42) [59]. Interestingly, treatment of the adducts with magnesium monoperoxyphthalate (MMPP) gave the corresponding azoxy compounds in excellent yields (up to 99%) and with complete regioselectivities and excellent enantioselectivities (up to 99% ee). A stereochemical model
Graphical Abstract
Figure 1: 3-Hydroxyoxindole-containing natural products and biologically active molecules.
Scheme 1: Chiral CNN pincer Pd(II) complex 1 catalyzed asymmetric allylation of isatins.
Scheme 2: Asymmetric allylation of ketimine catalyzed by the chiral CNN pincer Pd(II) complex 2.
Scheme 3: Pd/L1 complex-catalyzed asymmetric allylation of 3-O-Boc-oxindoles.
Scheme 4: Cu(OTf)2-catalyzed asymmetric direct addition of acetonitrile to isatins.
Scheme 5: Chiral tridentate Schiff base/Cu complex catalyzed asymmetric Friedel–Crafts alkylation of isatins ...
Scheme 6: Guanidine/CuI-catalyzed asymmetric alkynylation of isatins with terminal alkynes.
Scheme 7: Asymmetric intramolecular direct hydroarylation of α-ketoamides.
Scheme 8: Plausible catalytic cycle for the direct hydroarylation of α-ketoamides.
Scheme 9: Ir-catalyzed asymmetric arylation of isatins with arylboronic acids.
Scheme 10: Enantioselective decarboxylative addition of β-ketoacids to isatins.
Scheme 11: Ruthenium-catalyzed hydrohydroxyalkylation of olefins and 3-hydroxy-2-oxindoles.
Scheme 12: Proposed catalytic mechanism and stereochemical model.
Scheme 13: In-catalyzed allylation of isatins with stannylated reagents.
Scheme 14: Modified protocol for the synthesis of allylated 3-hydroxyoxindoles.
Scheme 15: Hg-catalyzed asymmetric allylation of isatins with allyltrimethylsilanes.
Scheme 16: Enantioselective additions of organoborons to isatins.
Scheme 17: Asymmetric aldol reaction of isatins with cyclohexanone.
Scheme 18: Enantioselective aldol reactions of aliphatic aldehydes with isatin derivatives and the plausible t...
Scheme 19: Enantioselective aldol reaction of isatins and 2,2-dimethyl-1,3-dioxan-5-one.
Scheme 20: Asymmetric aldol reactions between ketones and isatins.
Scheme 21: Phenylalanine lithium salt-catalyzed asymmetric synthesis of 3-alkyl-3-hydroxyoxindoles.
Scheme 22: Aldolization between isatins and dihydroxyacetone derivatives.
Scheme 23: One-pot asymmetric synthesis of convolutamydine A.
Scheme 24: Asymmetric aldol reactions of cyclohexanone and acetone with isatins.
Scheme 25: Aldol reactions of acetone with isatins.
Scheme 26: Aldol reactions of ketones with isatins.
Scheme 27: Enantioselective allylation of isatins.
Scheme 28: Asymmetric aldol reaction of trifluoromethyl α-fluorinated β-keto gem-diols with isatins.
Scheme 29: Plausible mechanism proposed for the asymmetric aldol reaction.
Scheme 30: Asymmetric aldol reaction of 1,1-dimethoxyacetone with isatins.
Scheme 31: Enantioselective Friedel-Crafts reaction of phenols with isatins.
Scheme 32: Enantioselective addition of 1-naphthols with isatins.
Scheme 33: Enantioselective aldol reaction between 3-acetyl-2H-chromen-2-ones and isatins.
Scheme 34: Stereoselective Mukaiyama–aldol reaction of fluorinated silyl enol ethers with isatins.
Scheme 35: Asymmetric vinylogous Mukaiyama–aldol reaction between 2-(trimethylsilyloxy)furan and isatins.
Scheme 36: β-ICD-catalyzed MBH reactions of isatins with maleimides.
Scheme 37: β-ICD-catalyzed MBH reactions of 7-azaisatins with maleimides and activated alkenes.
Scheme 38: Enantioselective aldol reaction of isatins with ketones.
Scheme 39: Direct asymmetric vinylogous aldol reactions of allyl ketones with isatins.
Scheme 40: Enantioselective aldol reactions of ketones with isatins.
Scheme 41: The MBH reaction of isatins with α,β-unsaturated γ-butyrolactam.
Scheme 42: Reactions of tert-butyl hydrazones with isatins followed by oxidation.
Scheme 43: Aldol reactions of isatin derivatives with ketones.
Scheme 44: Enantioselective decarboxylative cyanomethylation of isatins.
Scheme 45: Catalytic kinetic resolution of 3-hydroxy-3-substituted oxindoles.
Scheme 46: Lewis acid catalyzed Friedel–Crafts alkylation of 3-hydroxy-2-oxindoles with electron-rich phenols.
Scheme 47: Lewis acid catalyzed arylation of 3-hydroxyoxindoles with aromatics.
Scheme 48: Synthetic application of 3-arylated disubstituted oxindoles in the construction of core structures ...
Scheme 49: CPA-catalyzed dearomatization and arylation of 3-indolyl-3-hydroxyoxindoles with tryptamines and 3-...
Scheme 50: CPA-catalyzed enantioselective decarboxylative alkylation of β-keto acids with 3-hydroxy-3-indolylo...
Scheme 51: BINOL-derived imidodiphosphoric acid-catalyzed enantioselective Friedel–Crafts reactions of indoles...
Scheme 52: CPA-catalyzed enantioselective allylation of 3-indolylmethanols.
Scheme 53: 3-Indolylmethanol-based substitution and cycloaddition reactions.
Scheme 54: CPA-catalyzed asymmetric [3 + 3] cycloaddtion reactions of 3-indolylmethanols with azomethine ylide...
Scheme 55: CPA-catalyzed three-component cascade Michael/Pictet–Spengler reactions of 3-indolylmethanols and a...
Scheme 56: Acid-promoted chemodivergent and stereoselective synthesis of diverse indole derivatives.
Scheme 57: CPA-catalyzed asymmetric formal [3 + 2] cycloadditions.
Scheme 58: CPA-catalyzed enantioselective cascade reactions for the synthesis of C7-functionlized indoles.
Scheme 59: Lewis acid-promoted Prins cyclization of 3-allyl-3-hydroxyoxindoles with aldehydes.
Scheme 60: Ga(OTf)3-catalyzed reactions of allenols and phenols.
Scheme 61: I2-catalyzed construction of pyrrolo[2.3.4-kl]acridines from enaminones and 3-indolyl-3-hydroxyoxin...
Scheme 62: CPA-catalyzed asymmetric aza-ene reaction of 3-indolylmethanols with cyclic enaminones.
Scheme 63: Asymmetric α-alkylation of aldehydes with 3-indolyl-3-hydroxyoxindoles.
Scheme 64: Organocatalytic asymmetric α-alkylation of enolizable aldehydes with 3-indolyl-3-hydroxyoxindoles a...
Magnesium bis(monoperoxyphthalate) hexahydrate as mild and efficient oxidant for the synthesis of selenones
- Andrea Temperini,
- Massimo Curini,
- Ornelio Rosati and
- Lucio Minuti
Beilstein J. Org. Chem. 2014, 10, 1267–1271, doi:10.3762/bjoc.10.127
- Abstract A new, efficient and mild method for the direct oxidation of selenides to selenones using magnesium bis(monoperoxyphthalate) hexahydrate (MMPP) has been developed. Noteworthy this transformation proceeds at room temperature, employs a cheap and safety oxidant and has a broad functional group
- investigated the use of magnesium bis(monoperoxyphthalate) hexahydrate (MMPP) as a new oxidant for the straightforward conversion of selenides 1 to selenones 2 under mild experimental conditions. Magnesium bis(monoperoxyphthalate) hexahydrate is a cheap commercially available, relatively stable and easy to use
- oxidant and it has been employed for the selective oxidation of sulfides to the corresponding sulfoxides, for the preparation of α-methylenecyclohexane [16] and glycosyl sulfoxides [17]. Compared to the widely used peroxy acid MCPBA, MMPP has similar chemical properties, but it is a halogen-free reagent
Graphical Abstract
Scheme 1: General transformation of selenides to selenones.
Scheme 2: Phenylselenone 2 as useful leaving group for the synthesis of different organic molecules.
Polar reactions of acyclic conjugated bisallenes
- Reiner Stamm and
- Henning Hopf
Beilstein J. Org. Chem. 2013, 9, 36–48, doi:10.3762/bjoc.9.5
- . The oxidation of the tetramethylbisallene 2 was carried out with magnesium monoperoxy phthalate (MMPP) since we had also observed the formation of addition products of 2 (m-chlorobenzoates) when we used MCPBA for epoxidation. Indeed, ketone 36 could be obtained in 80% yield with MMPP (GC analysis
- . Since the analytical and spectroscopic data are incomplete in the literature [26], these data are given in full in Supporting Information File 1. The next bisallene to be oxidized was the fully substituted hexamethyl derivative 7, prepared as described in Scheme 2. Reaction with 0.5 equiv of MMPP
- resulted in the formation of 68% of 38 and a trace amount of the epoxide 39 (8%), while 24% of the substrate was recovered (GC analysis). Since the complete separation of the two products was difficult, the experiment was repeated with excess MMPP (1.5 equiv); in this case the yield of 39 was 62% and the
Graphical Abstract
Scheme 1: The alkylated conjugated bisallenes 1– 3 as model systems for polar reactions.
Scheme 2: Alkylation and silylation of 2.
Scheme 3: Allylation of the monoanion 4.
Scheme 4: Metalation/silylation of hydrocarbon 3.
Scheme 5: Quenching of 4 with DMF and acetone.
Scheme 6: Further reactions of 2/4 with various electrophiles.
Scheme 7: Oxidation of conjugated bisallenes with different oxidizing agents according to [26].
Scheme 8: Oxidation of 2, 7 and 5 with MMPP.
Scheme 9: Oxidation of the asymmetric bisallene 3 by air.
Scheme 10: Epoxidation of the disilylbisallenes 11 and 12.
Scheme 11: The addition of HCl and HBr to the bisallenes 2 and 5.
Scheme 12: The addition of bromine to the bisallene 2.
Scheme 13: The addition of iodine to the conjugated bisallenes 61, 2 and 3.
Scheme 14: Addition of chlorosulfonyl isocyanate (CSI, 66) to allenes.
Efficient oxidation of oleanolic acid derivatives using magnesium bis(monoperoxyphthalate) hexahydrate (MMPP): A convenient 2-step procedure towards 12-oxo-28-carboxylic acid derivatives
- Jorge A. R. Salvador,
- Vânia M. Moreira,
- Rui M. A. Pinto,
- Ana S. Leal and
- José A. Paixão
Beilstein J. Org. Chem. 2012, 8, 164–169, doi:10.3762/bjoc.8.17
- /bjoc.8.17 Abstract A new, straightforward and high yielding procedure to convert oleanolic acid derivatives into the corresponding δ-hydroxy-γ-lactones, by using the convenient oxidizing agent magnesium bis(monoperoxyphthalate) hexahydrate (MMPP) in refluxing acetonitrile, is reported. In addition, a
- : bismuth(III) triflate; δ-hydroxy-γ-lactones; MMPP; oleanolic acid; triterpenoid; Findings The molecular diversity that arises from research into natural products represents a valuable tool for driving drug discovery and development [1][2]. In this context, pentacyclic triterpenoids are currently regarded
- (monoperoxyphthalate) hexahydrate (MMPP) is commercially available, inexpensive and relatively stable [32][33][34] and has been used in the oxidation of various functional groups [35][36][37][38][39][40][41][42]. This oxidant is non-shock-sensitive and non-deflagrating [43]. Moreover, its use greatly simplifies the
Graphical Abstract
Figure 1: ORTEP diagram of compound 4 (50% probability level, H atoms of arbitrary sizes). The asymmetric uni...
Scheme 1: Sequential 2-step synthesis of 3,12-dioxoolean-28-oic acid (11) directly from 3-oxooleanolic acid (1...
Figure 2: ORTEP diagram of compound 11 (50% probability level, H atoms of arbitrary sizes).
