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Search for "amino aldehyde" in Full Text gives 6 result(s) in Beilstein Journal of Organic Chemistry.
Solution-phase automated synthesis of an α-amino aldehyde as a versatile intermediate
- Hisashi Masui,
- Sae Yosugi,
- Shinichiro Fuse and
- Takashi Takahashi
Beilstein J. Org. Chem. 2017, 13, 106–110, doi:10.3762/bjoc.13.13
Graphical Abstract
Scheme 1: Automated synthesis of 4a.
Figure 1: Full picture of ChemKonzert, showing two reaction vessels (RF1 and RF2), a centrifugal separator (S...
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
Graphical Abstract
Scheme 1: The proposed mechanism of the Passerini reaction.
Scheme 2: The PADAM-strategy to α-hydroxy-β-amino amide derivatives 7. An additional oxidation provides α-ket...
Scheme 3: The general accepted Ugi-mechanism.
Scheme 4: Three commonly applied Ugi/cyclization approaches. a) UDC-process, b) UAC-sequence, c) UDAC-combina...
Scheme 5: Ugi reaction that involves the condensation of Armstrong’s convertible isocyanide.
Scheme 6: Mechanism of the U-4C-3CR towards bicyclic β-lactams.
Scheme 7: The Ugi 4C-3CR towards oxabicyclo β-lactams.
Scheme 8: Ugi MCR between an enantiopure monoterpene based β-amino acid, aldehyde and isocyanide resulting in...
Scheme 9: General MCR for β-lactams in water.
Scheme 10: a) Ugi reaction for β-lactam-linked peptidomimetics. b) Varying the β-amino acid resulted in β-lact...
Scheme 11: Ugi-4CR followed by a Pd-catalyzed Sn2 cyclization.
Scheme 12: Ugi-3CR of dipeptide mimics from 2-substituted pyrrolines.
Scheme 13: Joullié–Ugi reaction towards 2,5-disubstituted pyrrolidines.
Scheme 14: Further elaboration of the Ugi-scaffold towards bicyclic systems.
Scheme 15: Dihydroxyproline derivatives from an Ugi reaction.
Scheme 16: Diastereoselective Ugi reaction described by Banfi and co-workers.
Scheme 17: Similar Ugi reaction as in Scheme 16 but with different acids and two chiral isocyanides.
Scheme 18: Highly diastereoselective synthesis of pyrrolidine-dipeptoids via a MAO-N/MCR-procedure.
Scheme 19: MAO-N/MCR-approach towards the hepatitis C drug telaprevir.
Scheme 20: Enantioselective MAO-U-3CR procedure starting from chiral pyrroline 64.
Scheme 21: Synthesis of γ-lactams via an UDC-sequence.
Scheme 22: Utilizing bifunctional groups to provide bicyclic γ-lactam-ketopiperazines.
Scheme 23: The Ugi reaction provided both γ- as δ-lactams depending on which inputs were used.
Scheme 24: The sequential Ugi/RCM with olefinic substrates provided bicyclic lactams.
Scheme 25: a) The structural and dipole similarities of the triazole unit with the amide bond. b) The copper-c...
Scheme 26: The Ugi/Click sequence provided triazole based peptidomimetics.
Scheme 27: The Ugi/Click reaction as described by Nanajdenko.
Scheme 28: The Ugi/Click-approach by Pramitha and Bahulayan.
Scheme 29: The Ugi/Click-combination by Niu et al.
Scheme 30: Triazole linked peptidomimetics obtained from two separate MCRs and a sequential Click reaction.
Scheme 31: Copper-free synthesis of triazoles via two MCRs in one-pot.
Scheme 32: The sequential Ugi/Paal–Knorr reaction to afford pyrazoles.
Scheme 33: An intramolecular Paal–Knorr condensation provided under basic conditions pyrazolones.
Scheme 34: Similar cyclization performed under acidic conditions provided pyrazolones without the trifluoroace...
Scheme 35: The Ugi-4CR towards 2,4-disubstituted thiazoles.
Scheme 36: Solid phase approach towards thiazoles.
Scheme 37: Reaction mechanism of formation of thiazole peptidomimetics containing an additional β-lactam moiet...
Scheme 38: The synthesis of the trisubstituted thiazoles could be either performed via an Ugi reaction with pr...
Scheme 39: Performing the Ugi reaction with DMB-protected isocyanide gave access to either oxazoles or thiazol...
Scheme 40: Ugi/cyclization-approach towards 2,5-disubstituted thiazoles. The Ugi reaction was performed with d...
Scheme 41: Further derivatization of the thiazole scaffold.
Scheme 42: Three-step procedure towards the natural product bacillamide C.
Scheme 43: Ugi-4CR to oxazoles reported by Zhu and co-workers.
Scheme 44: Ugi-based synthesis of oxazole-containing peptidomimetics.
Scheme 45: TMNS3 based Ugi reaction for peptidomimics containing a tetrazole.
Scheme 46: Catalytic cycle of the enantioselective Passerini reaction towards tetrazole-based peptidomimetics.
Scheme 47: Tetrazole-based peptidomimetics via an Ugi reaction and a subsequent sigmatropic rearrangement.
Scheme 48: Resin-bound Ugi-approach towards tetrazole-based peptidomimetics.
Scheme 49: Ugi/cyclization approach towards γ/δ/ε-lactam tetrazoles.
Scheme 50: Ugi-3CR to pipecolic acid-based peptidomimetics.
Scheme 51: Staudinger–Aza-Wittig/Ugi-approach towards pipecolic acid peptidomimetics.
Figure 1: The three structural isomers of diketopiperazines. The 2,5-DKP isomer is most common.
Scheme 52: UDC-approach to obtain 2,5-DKPs, either using Armstrong’s isocyanide or via ethylglyoxalate.
Scheme 53: a) Ugi reaction in water gave either 2,5-DKP structures or spiro compounds. b) The Ugi reaction in ...
Scheme 54: Solid-phase approach towards diketopiperazines.
Scheme 55: UDAC-approach towards DKPs.
Scheme 56: The intermediate amide is activated as leaving group by acid and microwave assisted organic synthes...
Scheme 57: UDC-procedure towards active oxytocin inhibitors.
Scheme 58: An improved stereoselective MCR-approach towards the oxytocin inhibitor.
Scheme 59: The less common Ugi reaction towards DKPs, involving a Sn2-substitution.
Figure 2: Spatial similarities between a natural β-turn conformation and a DKP based β-turn mimetic [158].
Scheme 60: Ugi-based syntheses of bicyclic DKPs. The amine component is derived from a coupling between (R)-N-...
Scheme 61: Ugi-based synthesis of β-turn and γ-turn mimetics.
Figure 3: Isocyanide substituted 3,4-dihydropyridin-2-ones, dihydropyridines and the Freidinger lactams. Bio-...
Scheme 62: The mechanism of the 4-CR towards 3,4-dihydropyridine-2-ones 212.
Scheme 63: a) Multiple MCR-approach to provide DHP-peptidomimetic in two-steps. b) A one-pot 6-CR providing th...
Scheme 64: The MCR–alkylation–MCR procedure to obtain either tetrapeptoids or depsipeptides.
Scheme 65: U-3CR/cyclization employing semicarbazone as imine component gave triazine based peptidomimetics.
Scheme 66: 4CR towards triazinane-diones.
Scheme 67: The MCR–alkylation–IMCR-sequence described by our group towards triazinane dione-based peptidomimet...
Scheme 68: Ugi-4CR approaches followed by a cyclization to thiomorpholin-ones (a) and pyrrolidines (b).
Scheme 69: UDC-approach for benzodiazepinones.
Scheme 70: Ugi/Mitsunobu sequence to BDPs.
Scheme 71: A UDAC-approach to BDPs with convertible isocyanides. The corresponding amide is cleaved by microwa...
Scheme 72: microwave assisted post condensation Ugi reaction.
Scheme 73: Benzodiazepinones synthesized via the post-condensation Ugi/ Staudinger–Aza-Wittig cyclization.
Scheme 74: Two Ugi/cyclization approaches utilizing chiral carboxylic acids. Reaction (a) provided the product...
Scheme 75: The mechanism of the Gewald-3CR includes three base-catalysed steps involving first a Knoevnagel–Co...
Scheme 76: Two structural 1,4-thienodiazepine-2,5-dione isomers by U-4CR/cyclization.
Scheme 77: Tetrazole-based diazepinones by UDC-procedure.
Scheme 78: Tetrazole-based BDPs via a sequential Ugi/hydrolysis/coupling.
Scheme 79: MCR synthesis of three different tricyclic BPDs.
Scheme 80: Two similar approaches both involving an Ugi reaction and a Mitsunobu cyclization.
Scheme 81: Mitsunobu–Ugi-approach towards dihydro-1,4-benzoxazepines.
Scheme 82: Ugi reaction towards hetero-aryl fused 5-oxo-1,4-oxazepines.
Scheme 83: a) Ugi/RCM-approach towards nine-membered peptidomimetics b) Sequential peptide-coupling, deprotect...
Scheme 84: Ugi-based synthesis towards cyclic RGD-pentapeptides.
Scheme 85: Ugi/MCR-approach towards 12–15 membered macrocycles.
Scheme 86: Stereoselective Ugi/RCM approach towards 16-membered macrocycles.
Scheme 87: Passerini/RCM-sequence to 22-membered macrocycles.
Scheme 88: UDAC-approach towards 12–18-membered depsipeptides.
Figure 4: Enopeptin A with its more active derivative ADEP-4.
Scheme 89: a) The Joullié–Ugi-approach towards ADEP-4 derivatives b) Ugi-approach for the α,α-dimethylated der...
Scheme 90: Ugi–Click-strategy for 15-membered macrocyclic glyco-peptidomimetics.
Scheme 91: Ugi/Click combinations provided macrocycles containing both a triazole and an oxazole moiety.
Scheme 92: a) A solution-phase procedure towards macrocycles. b) Alternative solid-phase synthesis as was repo...
Scheme 93: Ugi/cyclization towards cyclophane based macrocycles.
Scheme 94: PADAM-strategy towards eurystatin A.
Scheme 95: PADAM-approach for cyclotheanamide.
Scheme 96: A triple MCR-approach affording RGD-pentapeptoids.
Scheme 97: Ugi-MiBs-approach towards peptoid macrocycles.
Scheme 98: Passerini-based MiB approaches towards macrocycles 345 and 346.
Scheme 99: Macrocyclic peptide formation by the use of amphoteric aziridine-based aldehydes.
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
- configurationally labile amino aldehyde intermediates [55][56]. Basically any carbamate or amide protecting group (= PG) orthogonal to the benzyl moiety would be suitable for this strategy. Furthermore, we decided to surrender protection of the OH functions in the synthesis of intermediates D and C in order to
Graphical Abstract
Figure 1: Natural products and other bioactive piperidine derivatives of type B.
Figure 2: Retrosynthetic analysis of piperidines B (X = OH or leaving group, PG = protecting group).
Scheme 1: Synthesis of the protected amino acids 2. (a) KOH for 1b. b) PG–X = Cbz–Cl (1a–c), Boc2O (1d).
Scheme 2: Synthesis of hydroxy ketones 7 (R = Me (a), Bn (b), Ph (c) and EtSMe (d); PG = Cbz (a–c), Boc (d)).
Scheme 3: Synthesis of amides 5e and 5f and ketone 7e.
Scheme 4: Synthesis of amino alcohols syn-9a–d and oxazolidinone 10a. (for 7a–c conditions A: H2 (1 atm), Pd/...
Scheme 5: Competition between the Michaelis–Arbuzow process and the desired cyclodehydration of amino alcohol...
Scheme 6: Initial synthesis of the trans-piperidinol 11a in diminished enantiopurity. aThe amino alcohol 9a o...
Scheme 7: Synthesis of trans-piperidinol 11a in excellent ee.
Scheme 8: Synthesis of L-733,060·HCl.
A versatile and efficient approach for the synthesis of chiral 1,3-nitroamines and 1,3-diamines via conjugate addition to new (S,E)-γ-aminated nitroalkenes derived from L-α-amino acids
- Vera Lúcia Patrocinio Pereira,
- André Luiz da Silva Moura,
- Daniel Pais Pires Vieira,
- Leandro Lara de Carvalho,
- Eliz Regina Bueno Torres and
- Jeronimo da Silva Costa
Beilstein J. Org. Chem. 2013, 9, 832–837, doi:10.3762/bjoc.9.95
- alcohol; amino aldehyde; azide addition; Baylis–Hillman reaction; cyanide addition; Michael addition; Introduction Nitroalkenes constitute a class of organic compounds that present exceptional versatility in organic synthesis [1][2][3][4]. They are reactive in Michael reactions with a wide variety of
Graphical Abstract
Scheme 1: Reagents and conditions: (i) K2CO3, EtOH/H2O 5:1, BnBr, 100 °C, 12 h (90–99%). (ii) (a) LiAlH4, THF...
Figure 1: Chiral HPLC analysis: Chiralpak AD-H; n-hexane/2-propanol 99:1 (0.6 mL/min), T = 25 °C; UV–vis dete...
Scheme 2: Synthesis of 1,3-diamines 14a,b. (i) NaBH4/NiCl2·6H2O/MeOH/3 h/rt.
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
- steps via the Fleet protocol [55]. The tandem RCM/dihydroxylation sequence was also applied by Davis et al. in the synthesis of (−)-2,3-trans-3,4-cis-dihydroxyproline. In this case, an α-amino aldehyde, prepared by addition of a 1,3-dithiane to a chiral N-sulfinyl imine, was used as the chiral starting
Graphical Abstract
Scheme 1: Well-defined Mo- and Ru-alkylidene metathesis catalysts.
Scheme 2: Representative pyrrolidine-based iminocyclitols.
Scheme 3: Synthesis of (±)-(2R*,3R*,4S*)-2-hydroxymethylpyrrolidin-3,4-diol (18), (±)-2-hydroxymethylpyrrolid...
Scheme 4: Synthesis of enantiopure iminocyclitol (−)-(2S,3R,4S,5S)-2,5-dihydroxymethylpyrrolidin-3,4-diol (23...
Scheme 5: Synthesis of 1,4-dideoxy-1,4-imino-D-allitol (29) and formal synthesis of (2S,3R,4S)-3,4-dihydroxyp...
Scheme 6: Synthesis of iminocyclitols 35 and 36.
Scheme 7: Total synthesis of iminocyclitols 40 and 44.
Scheme 8: Synthesis of 2,5-dideoxy-2,5-imino-D-mannitol [(+)-DMDP] (49) and (−)-bulgecinine (50).
Scheme 9: Synthesis of (+)-broussonetine G (53).
Scheme 10: Structural features of broussonetines 54.
Scheme 11: Synthesis of broussonetines by cross-metathesis.
Scheme 12: Representative piperidine-based iminocyclitols.
Scheme 13: Total synthesis of 1-deoxynojirimycin (62) and 1-deoxyaltronojirimycin (65).
Scheme 14: Synthesis by RCM of 1-deoxymannonojirimycin (63) and 1-deoxyallonojirimycin (66).
Scheme 15: Total synthesis of (+)-1-deoxynojirimycin (62).
Scheme 16: Synthesis of ent-1,6-dideoxynojirimycin (83) and 5-amino-1,5,6-trideoxyaltrose (84).
Scheme 17: Synthesis of 1-deoxygalactonojirimycin (64), 1-deoxygulonojirimycin (91) and 1-deoxyidonojirimycin (...
Scheme 18: Synthesis of L-1-deoxyaltronojirimycin (96).
Scheme 19: Synthesis of 1-deoxymannonojirimycin (63) and 1-deoxyaltronojirimycin (65).
Scheme 20: Synthesis of 5-des(hydroxymethyl)-1-deoxymannonojirimycin (111) and 5-des(hydroxymethyl)-1-deoxynoj...
Scheme 21: Synthesis of D-1-deoxygulonojirimycin (91) and L-1-deoxyallonojirimycin (122).
Scheme 22: Total synthesis of fagomine (129), 3-epi-fagomine (126) and 3,4-di-epi-fagomine (130).
Scheme 23: Total synthesis of (+)-adenophorine (135).
Scheme 24: Total synthesis of (+)-5-deoxyadenophorine (138) and analogues 142–145.
Scheme 25: Synthesis by RCM of 1,6-dideoxy-1,6-iminoheptitols 148 and 149.
Scheme 26: Synthesis by RCM of oxazolidinyl azacycles 152 and 154.
Scheme 27: Representative azepane-based iminocyclitols.
Scheme 28: Synthesis of hydroxymethyl-1-(4-methylphenylsulfonyl)azepane 3,4,5-triol (169).
Scheme 29: Synthesis by RCM of tetrahydropyridin-3-ol 171 and tetrahydroazepin-3-ol 173.
An efficient synthesis of novel pyrano[2,3-d]- and furopyrano[2,3-d]pyrimidines via indium- catalyzed multi- component domino reaction
- Dipak Prajapati and
- Mukut Gohain
Beilstein J. Org. Chem. 2006, 2, No. 11, doi:10.1186/1860-5397-2-11
- type of cycloaddition using an amino aldehyde and a benzyl enol ether in presence of ethylene diammonium acetate and triethyl orthoformate has been reported earlier but this method has its own merits and limitations.[36] Results and Discussions On treatment of 1,3-dimethylbarbituric acid 1, 4
Graphical Abstract
Scheme 1: Reagents and conditions: i) 1 mol% InCl3, acetonitrile:water (3:1)
Scheme 2: Reagents and conditions: i) 1 mol% InCl3, room temperature
