Synthesis of aromatic glycoconjugates. Building blocks for the construction of combinatorial glycopeptide libraries

• Markus Nörrlinger and
• Thomas Ziegler

Beilstein J. Org. Chem. 2014, 10, 2453–2460, doi:10.3762/bjoc.10.256

• focus was on glycosylated amino acid building blocks derived from aspartic acid and from the PNA-like N-(2-aminoethyl)glycine (AEG) backbone to which the sugar moieties were attached through either simple alkyl chains [5][6], amino alcohols [7][8] or 1,2,3-triazoles [9][10][11]. These building blocks

One-pot stereoselective synthesis of α,β-differentiated diamino esters via the sequence of aminochlorination, aziridination and intermolecular S_N2 reaction

• Yiwen Xiong,
• Ping Qian,
• Chenhui Cao,
• Haibo Mei,
• Jianlin Han,
• Guigen Li and
• Yi Pan

Beilstein J. Org. Chem. 2014, 10, 1802–1807, doi:10.3762/bjoc.10.189

• corresponding β,γ-amino alcohols and vicinal diamines. α,β-Diamino acid derivatives have been served as organocatalysts, chiral ligands, chiral auxiliaries for asymmertric synthesis [10][11][12], as well as synthetic fragments for peptides and natural products [13]. Mannich-type addition reactions of α-amino

Rational design of cyclopropane-based chiral PHOX ligands for intermolecular asymmetric Heck reaction

• Marina Rubina,
• William M. Sherrill,
• Alexey Yu. Barkov and
• Michael Rubin

Beilstein J. Org. Chem. 2014, 10, 1536–1548, doi:10.3762/bjoc.10.158

• system. Indeed, a number of previously reported PHOX ligands derived from tert-leucinol were shown to provide superior enantioselectivities compared to their analogues obtained from less bulky amino alcohols [54][57][59]. However, the arylation carried out in the presence of L3 proceeded much more

Synthesis of 1-[bis(trifluoromethyl)phosphine]-1’-oxazolinylferrocene ligands and their application in regio- and enantioselective Pd-catalyzed allylic alkylation of monosubstituted allyl substrates

• Zeng-Wei Lai,
• Rong-Fei Yang,
• Ke-Yin Ye,
• Hongbin Sun and
• Shu-Li You

Beilstein J. Org. Chem. 2014, 10, 1261–1266, doi:10.3762/bjoc.10.126

• (COCl)2 and then chiral amino alcohols yielded the amide intermediates which were transformed to their corresponding 1-bromo-1’-oxazolinylferrocenes 3. Eventually, lithium–bromide exchange of 3 with n-BuLi at −78 °C, followed by quenching with P(OPh)3, provided the phosphonite intermediates which were

Homogeneous and heterogeneous photoredox-catalyzed hydroxymethylation of ketones and keto esters: catalyst screening, chemoselectivity and dilution effects

• Axel G. Griesbeck and
• Melissa Reckenthäler

Beilstein J. Org. Chem. 2014, 10, 1143–1150, doi:10.3762/bjoc.10.114

• product without the need of sacrificial components. The latter process proceeds with a high degree of atom economy [16]. We have recently demonstrated this for the azido-hydroperoxidation of alkenes, a convenient method for the synthesis of 1,2-amino alcohols [17][18]. In the field of C–C coupling

• contrast to that, photochemical redox activation is possible in the presence of titanium(IV) catalysts [19][20][21][22]. As shown in a series of papers by Sato and coworkers, carbonyl compounds 1 as well as imines couple with methanol to give the 1,2-diols or 1,2-amino alcohols, respectively, when

Isocyanide-based multicomponent reactions towards cyclic constrained peptidomimetics

• Gijs Koopmanschap,
• Eelco Ruijter and
• Romano V.A. Orru

Beilstein J. Org. Chem. 2014, 10, 544–598, doi:10.3762/bjoc.10.50

• -isomer over the 1,5-isomer [85]. In 2010, Nenajdenko et al. described an Ugi/Click-approach using chiral isocyanoazides, which in turn were derived from L-amino alcohols [85]. The Ugi-products were obtained in good yields, with high diastereoselectivity (de >99%). A follow-up Click reaction using 10 mol

Concise, stereodivergent and highly stereoselective synthesis of cis- and trans-2-substituted 3-hydroxypiperidines – development of a phosphite-driven cyclodehydration

• Peter H. Huy,
• Julia C. Westphal and
• Ari M. P. Koskinen

Beilstein J. Org. Chem. 2014, 10, 369–383, doi:10.3762/bjoc.10.35

• overcoming separation difficulties usually associated to triphenylphosphine oxide. Keywords: amino acids; asymmetric synthesis; cyclodehydration; hydroxypiperidines; natural products; one-pot; Introduction 1,2-Amino alcohols of the type A (Figure 1) represent a frequent core motif of many pharmacologically

• 5e (along with 30% of reisolated starting material), illustrating the tendency of reagent 6 to attack the side chain ester moiety. Synthesis of syn-amino alcohols C Already the NaBH4 reduction (in MeOH at −40/0 °C) of ketones 7a and 7b and subsequent hydrogenolysis of the Cbz-group in one-pot

• delivered the syn-amino alcohols 9a and 9b in good diastereomeric ratios (around 11:1 syn/anti, compare Scheme 4). In contrast the NaBH4 reduction of ketone 7c under identical conditions gave diol 9c without any selectivity (dr = 1.3:1). To our delight, reduction of the ketones 7a and 7b with L-Selectride

Garner’s aldehyde as a versatile intermediate in the synthesis of enantiopure natural products

• Mikko Passiniemi and
• Ari M.P. Koskinen

Beilstein J. Org. Chem. 2013, 9, 2641–2659, doi:10.3762/bjoc.9.300

• ]. We have recently reviewed the literature on the synthesis of 1,2-vicinal amino alcohols [53]. Use of Garner’s aldehyde for the synthesis of non-natural amino acids through ethynylglycine has been reviewed [54]. In the following section, significant findings in the use of 1 as an electrophile and

• synthesis. Simple addition reactions to the carbonyl group give access to vicinal amino alcohols, important building blocks for many natural products. Another possibility for carbon chain elongation are olefination reactions, which often lead to epimerization of the α-stereocenter. As with the alkylations

A one-pot synthesis of 3-trifluoromethyl-2-isoxazolines from trifluoromethyl aldoxime

• Raoni S. B. Gonçalves,
• Michael Dos Santos,
• Guillaume Bernadat,
• Danièle Bonnet-Delpon and
• Benoit Crousse

Beilstein J. Org. Chem. 2013, 9, 2387–2394, doi:10.3762/bjoc.9.275

• yield the corresponding trifluoromethylated γ-amino alcohols. Keywords: aldoxime; amino alcohol; fluorine; isoxazole; isoxazoline; organo-fluorine; Introduction 2-Isoxazolines are five-membered heterocyclic compounds that have been widely applied in medicinal and organic chemistry. This nucleus is

• supply a variety of organic functionalities including γ-amino alcohols [12], β-amino acids [13], β-hydroxy ketones [14][15] and β-hydroxy nitriles [14][15]. Fluorinated compounds play a central role in different branches of chemistry [16]. The incorporation of a fluorine atom into bioactive molecules

• order to prepare the corresponding trifluoromethylated γ-amino alcohols. The major and almost the only route to synthesize these amino alcohols is the reduction of β-aminocarbonyl compounds prepared from Mannich-type reactions [46][47][48]. The ring opening of 2-methyl-3-trifluoromethylisoxazolines by

Direct electrophilic N-trifluoromethylthiolation of amines with trifluoromethanesulfenamide

• Sébastien Alazet,
• Kevin Ollivier and
• Thierry Billard

Beilstein J. Org. Chem. 2013, 9, 2354–2357, doi:10.3762/bjoc.9.270

• volatility, some compounds (3h and 3i) have not been isolated. Imines can be also trifluoromethylthiolated in good yields (3m). Even if our first developed method is compatible with primary amines [37], they can also react under these new conditions, as illustrated with the aniline (3n). Amino alcohols and

Flow synthesis of phenylserine using threonine aldolase immobilized on Eupergit support

• Jagdish D. Tibhe,
• Hui Fu,
• Timothy Noël,
• Qi Wang,
• Jan Meuldijk and
• Volker Hessel

Beilstein J. Org. Chem. 2013, 9, 2168–2179, doi:10.3762/bjoc.9.254

• development of an enzymatic bioreaction and found that the dynamics of a biochemical reaction can be studied in a few seconds [35]. Although many promising routes have been developed for the synthesis of chiral α-amino alcohols, these often depend on the use of toxic and expensive chiral ligands coupled to

Organocatalyzed enantioselective desymmetrization of aziridines and epoxides

• Ping-An Wang

Beilstein J. Org. Chem. 2013, 9, 1677–1695, doi:10.3762/bjoc.9.192

• including cinchona alkaloid derivatives, chiral phosphoric acids, chiral amino alcohols, chiral thioureas, chiral guanidines, and chiral 1,2,3-triazolium chlorides. In this review, the research work of enantioselective desymmetrization of meso-aziridines is organized into sections according to the employed

• activation mechanism of this desymmetrization was proposed. Chiral amino alcohols Lattanzi and colleagues [49] have also discovered the desymmetrization of meso-N-acylaziridines with benzenethiols in the presence of α,α-diaryl-L-prolinols (Figure 6, OC-22 to OC-25) to afford the products in good yields and

• -aziridines are plentiful and can be found in a diverse set of privileged structures, including cinchona alkaloids-based PTCs, L-proline-derived amino alcohols, chiral phosphorous acids, chiral thioureas, chiral guanidines, and chiral 1,2,3-triazolium chlorides. But for the desymmetrization of meso-epoxides

Efficient continuous-flow synthesis of novel 1,2,3-triazole-substituted β-aminocyclohexanecarboxylic acid derivatives with gram-scale production

• Sándor B. Ötvös,
• Ádám Georgiádes,
• István M. Mándity,
• Lóránd Kiss and
• Ferenc Fülöp

Beilstein J. Org. Chem. 2013, 9, 1508–1516, doi:10.3762/bjoc.9.172

• bioactive agents with anticancer, antibacterial, antiviral or analgesic effects (Figure 2) [25][26]. The alicyclic β-amino acids are key intermediates for the synthesis of a series of pharmaceutically relevant products [27], such as amino esters, amino alcohols, azides and heterocycles. Moreover, they are

Titanium-mediated reductive cross-coupling reactions of imines with terminal alkynes: An efficient route for the synthesis of stereodefined allylic amines

• Kebin Mao,
• Guoqin Fan,
• Yuanhong Liu,
• Shi Li,
• Xu You and
• Dan Liu

Beilstein J. Org. Chem. 2013, 9, 621–627, doi:10.3762/bjoc.9.69

• 1,2-amino alcohols [39]. These results prompted us to study the cross-coupling of imines with terminal alkynes by using the Ti(OiPr)4/2 c-C5H9MgCl reagent. In this paper, we describe the detailed results of these reactions (Scheme 1). Results and Discussion Synthesis of allylic amines by reductive

Efficient synthesis of β’-amino-α,β-unsaturated ketones

• Isabelle Abrunhosa-Thomas,
• Aurélie Plas,
• Nishanth Kandepedu,
• Pierre Chalard and
• Yves Troin

Beilstein J. Org. Chem. 2013, 9, 486–495, doi:10.3762/bjoc.9.52

• incorporating β-amino ketone functionality are prevalent in many natural products of biological importance [1]. This versatile synthon has been extensively used in the construction of β-amino acids [2], β-amino alcohols [3], and homoallylic amines [4][5], and can serve as building blocks for the preparation of

Polymerization of novel methacrylated anthraquinone dyes

• Christian Dollendorf,
• Susanne Katharina Kreth,
• Soo Whan Choi and
• Helmut Ritter

Beilstein J. Org. Chem. 2013, 9, 453–459, doi:10.3762/bjoc.9.48

• materials used for iris implants or other medical applications. Conclusion In conclusion, a series of novel anthraquinone based polymerizable dyes has been synthesized by nucleophilic aromatic substitution reactions of anthraquinone derivatives with several amino alcohols. Depending on the moieties that

Enantioselective total synthesis of (R)-(−)-complanine

• Krystal A. D. Kamanos and
• Jonathan M. Withey

Beilstein J. Org. Chem. 2012, 8, 1695–1699, doi:10.3762/bjoc.8.192

• with a γ-aminobutyric acid (GABA) derivative. Complanine is structurally related to the obscuraminols, isolated from another marine source, the ascidian Pseudodistoma obscurum [2]. Unlike complanine, however, these substances are simple amino alcohols that do not possess any other chemical

• was synthesized in a sequence of nine linear steps, beginning with (R)-malic acid [3]. As part of our research endeavours directed towards the organocatalytic synthesis of 1,2-amino alcohols, we have developed a new asymmetric strategy leading to (R)-(−)-complanine. This approach utilizes an

Exploring chemical diversity via a modular reaction pairing strategy

• Joanna K. Loh,
• Sun Young Yoon,
• Thiwanka B. Samarakoon,
• Alan Rolfe,
• Patrick Porubsky,
• Benjamin Neuenswander,
• Gerald H. Lushington and
• Paul R. Hanson

Beilstein J. Org. Chem. 2012, 8, 1293–1302, doi:10.3762/bjoc.8.147

• the diversification of these core scaffolds with a variety of chiral, non-racemic amines/amino alcohols, by intermolecular SNAr utilizing benzoxathiazocine 1,1-dioxide 4 as the test substrate (Table 1). A variety of reaction conditions (equiv of amine, presence of base, concentration of solvent, time

Asymmetric organocatalytic decarboxylative Mannich reaction using β-keto acids: A new protocol for the synthesis of chiral β-amino ketones

• Chunhui Jiang,
• Fangrui Zhong and
• Yixin Lu

Beilstein J. Org. Chem. 2012, 8, 1279–1283, doi:10.3762/bjoc.8.144

• ketones are an important class of building blocks for the synthesis of 1,3-amino alcohols [1][2], 1,3-amino acids [3] and other bioactive nature products [4][5][6]. Given their synthetic significance, methods for the asymmetric synthesis of β-amino ketones have been extensively investigated over the past

Synthesis of a library of tricyclic azepinoisoindolinones

• Bettina Miller,
• Shuli Mao,
• Kara M. George Rosenker,
• Joshua G. Pierce and
• Peter Wipf

Beilstein J. Org. Chem. 2012, 8, 1091–1097, doi:10.3762/bjoc.8.120

• ]. Yields and purities of amino alcohols 9{1–12} and 10{1–13} are summarized in Table 1. The 9{1–11}/10{1–11} isolated product ratios varied between 5:1 and 1.5:1, with no obvious trends discernable. Interestingly, for adamantyl amine 8{13}, only the corresponding 10{13} was isolated, most likely due to the

• ]. Conclusion A library of novel tricyclic isoindolinone amino alcohols was prepared in seven steps from commercially available starting materials. Key transformations include the addition of in situ generated alkenylalanes to an N-acyliminium ion derived from pivaloate 1, a tandem ring-closing metathesis

• 2 in the absence of Ti(OiPr)4 and isolation of hydroxy epoxide 6 after treatment with m-CPBA. Preparation and RCM reaction of bis-terminal diene analogue 7. Conversion of epoxide 5 to 1,2-amino alcohols. Library matrix of products 9{1–13} and 10{1–13} [isolated yield (%) and purity by ELSD

Carbohydrate-auxiliary assisted preparation of enantiopure 1,2-oxazine derivatives and aminopolyols

• Marcin Jasiński,
• Dieter Lentz and
• Hans-Ulrich Reissig

Beilstein J. Org. Chem. 2012, 8, 662–674, doi:10.3762/bjoc.8.74

• [58], and pyran derivatives [59]. Gratifyingly, the treatment of tetrahydro-2H-1,2-oxazine derivatives 12 and 13 with an excess of SmI2 in tetrahydrofuran smoothly provided the expected amino alcohols 16 and 17 in excellent yields (Scheme 5). In order to compare the behaviour of a compound still

• bearing the N-auxiliary, we converted tetrahydro-2H-1,2-oxazine 7 into the O-benzylated derivative 18 under standard conditions (Scheme 6). Treatment of this protected compound with samarium diiodide furnished a complex mixture of products from which only the two amino alcohols 19 and 20 were isolated, in

Enantioselective supramolecular devices in the gas phase. Resorcin[4]arene as a model system

• Caterina Fraschetti,
• Matthias C. Letzel,
• Antonello Filippi,
• Maurizio Speranza and
• Jochen Mattay

Beilstein J. Org. Chem. 2012, 8, 539–550, doi:10.3762/bjoc.8.62

• . Cyclochiral resorcin[4]arenes. Studied (a) peptidoresorcin[4]arenes and (b) dipeptidic guests. Exchange rate constants (k × 10−11 cm3 molecule−1 s−1). Exchange rate constants (k × 10−10 cm3 molecule−1 s−1). Rate constant ratios (Equation 6). Overview of investigated amino acids, amino alcohols and amino acid

Synthesis of highly functionalized β-aminocyclopentanecarboxylate stereoisomers by reductive ring opening reaction of isoxazolines

• Melinda Nonn,
• Loránd Kiss,
• Reijo Sillanpää and
• Ferenc Fülöp

Beilstein J. Org. Chem. 2012, 8, 100–106, doi:10.3762/bjoc.8.10

• , University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary 10.3762/bjoc.8.10 Abstract A rapid and simple procedure was devised for the synthesis of multifunctionalized cyclic β-amino esters and γ-amino alcohols via the 1,3-dipolar cycloaddition of nitrile oxides to β-aminocyclopentenecarboxylates. The

• molecules such as β-hydroxyketones [7][8][9][10], amino alcohols or amino acids [11][12][13][14][15][16][17], etc. The multifunctionalized cyclic amino acids – e.g., the antibiotic Oryzoxymycin [18][19][20][21], the antiviral agents Tamiflu [22][23][24][25][26][27][28][29][30][31][32][33], Zanamivir and 2,3

• . When the reduction was carried out with NaBH4 in EtOH, three products were obtained: The epimerized isoxazoline-fused amino carboxylate 7 and amino alcohols 8 and 9 which were separated by chromatography and isolated (Scheme 2). Thus, this reaction did not lead to the formation of highly functionalized

Highly efficient gold(I)-catalyzed Overman rearrangement in water

• Dong Xing and
• Dan Yang

Beilstein J. Org. Chem. 2011, 7, 781–785, doi:10.3762/bjoc.7.88

• hydroxy groups (1h and 1i) efficiently underwent the desired rearrangement to afford the corresponding products, which are precursors for the synthesis of a variety of β-substituted β-amino alcohols (Table 2, entries 8 and 9). Compound 2j was also obtained in 71% yield under the reaction conditions from

Metathesis access to monocyclic iminocyclitol-based therapeutic agents

• Ileana Dragutan,
• Valerian Dragutan,
• Carmen Mitan,
• Hermanus C.M. Vosloo,
• Lionel Delaude and
• Albert Demonceau

Beilstein J. Org. Chem. 2011, 7, 699–716, doi:10.3762/bjoc.7.81

• the 6-membered N-heterocycle in 133. Protection of the amino alcohols trans-132 and cis-132, as the corresponding trans and cis oxazolidinones, afforded a mixture of diastereomers that were not separable on silica gel. After effecting RCM (2nd-generation Grubbs catalyst 5, 5 mol %) on this mixture