Amyloid-β probes: Review of structure–activity and brain-kinetics relationships

• Todd J. Eckroat,
• Abdelrahman S. Mayhoub and
• Sylvie Garneau-Tsodikova

Beilstein J. Org. Chem. 2013, 9, 1012–1044, doi:10.3762/bjoc.9.116

• analogue takes place inside an HPLC sample loop [43]. Diphenyl-1,2,4- and diphenyl-1,3,4-oxadiazoles The replacement of the stilbene ethylene linker with different heterocycles is a common strategy in medicinal chemistry used to improve the pharmacokinetics and/or pharmacodynamics of stilbenes (Scheme 5A

• ) [44][45][46]. In the case of Aβ probes, a series of 2,5-diphenyl-1,3,4-oxadiazoles 50a–f and 3,5-diphenyl-1,2,4-oxadiazoles 51a–e have been studied in this respect (Table 3 and Table 4). Among the 2,5-diphenyl-1,3,4-oxadiazoles, the dimethylamine analogue 50a (Ki = 20.1 ± 2.5 nM) and methoxy analogue

• -1,2,4-oxadiazole analogue 51c was more lipophilic than its 1,3,4 counterpart 50a (log P = 3.22 for 51c and 2.43 for 50a) [47]. In general, even though 3,5-diphenyl-1,2,4-oxadiazoles 51a–e show excellent affinity for Aβ aggregates in in vitro binding experiments (Ki = 4.3–47.1 nM), they show poorer brain

A new synthetic access to 2-N-(glycosyl)thiosemicarbazides from 3-N-(glycosyl)oxadiazolinethiones and the regioselectivity of the glycosylation of their oxadiazolinethione precursors

• El Sayed H. El Ashry,
• El Sayed H. El Tamany,
• Mohy El Din Abdel Fattah,
• Mohamed R. E. Aly,
• Ahmed T. A. Boraei and
• Axel Duerkop

Beilstein J. Org. Chem. 2013, 9, 135–146, doi:10.3762/bjoc.9.16

• →N migration of the glycosyl moiety in glycosylsulfanyloxadiazoles. (Benzylindolyl)glycosylsulfanyl-1,3,4-oxadiazoles could be thermally rearranged into the corresponding N-glycosides. These may either be converted into the corresponding (benzylindolyl)-2-N-(glycosyl)thiosemicarbazides (of type II

Liquid-crystalline heterodimesogens and ABA-heterotrimesogens comprising a bent 3,5-diphenyl-1,2,4-oxadiazole central unit

• Govindaswamy Shanker,
• Marko Prehm and
• Carsten Tschierske

Beilstein J. Org. Chem. 2012, 8, 472–485, doi:10.3762/bjoc.8.54

• crystals; 1,2,4-oxadiazoles; trimesogen; Introduction Liquid-crystalline (LC) dimers of low-molar-mass compounds formed by the coupling of two mesogenic segments are of contemporary interest [1][2][3][4]. These compounds exhibit fascinating properties, often different from the single mesogens, and they

• dimesogens only form tilted LC phases (SmC, NcybC), for Thia-Ox/5 with a relatively short spacer the tilt is significantly reduced (25°) compared to the related 2,5-diphenyl-1,2,4-oxadiazoles without an attached rod-like unit (40–50°) [64][65]. In the dimesogen Thia-Ox/10, in which the two mesogenic units

Unusual behavior in the reactivity of 5-substituted-1H-tetrazoles in a resistively heated microreactor

• Bernhard Gutmann,
• Toma N. Glasnov,
• Tahseen Razzaq,
• Walter Goessler,
• Dominique M. Roberge and
• C. Oliver Kappe

Beilstein J. Org. Chem. 2011, 7, 503–517, doi:10.3762/bjoc.7.59

• method for the synthesis of 1,3,4-oxadiazoles [45][46]. In the NMP/AcOH/H2O solvent mixture, however, the formation of the oxadiazole 6 can scarcely compete with the intermolecular addition of water and oxadiazole 6 was therefore detectable only in minor amounts. Using NMP/AcOH as the solvent system, 2

Low temperature enantiotropic nematic phases from V-shaped, shape-persistent molecules

• Matthias Lehmann and
• Jens Seltmann

Beilstein J. Org. Chem. 2009, 5, No. 73, doi:10.3762/bjoc.5.73

• molecules with rigorously defined shape (bending angle) for the formation of the desired phase [5][7]. But it was not until 2004 that sufficient evidence was presented for biaxiality of nematic phases in the series of V-shaped oxadiazoles by X-ray diffraction and solid-state 2H NMR spectroscopy [8][9][10

2-Arylhydrazononitriles as building blocks in heterocyclic synthesis: A novel route to 2-substituted- 1,2,3-triazoles and 1,2,3-triazolo[4,5-b]pyridines

• Saleh M. Al-Mousawi and
• Moustafa Sh. Moustafa

Beilstein J. Org. Chem. 2007, 3, No. 12, doi:10.1186/1860-5397-3-12

• that can be assigned as 1,2,4-oxadiazolylphenylhydrazone structure 4 or the isomeric acetylamino-1,2,3-triazole structure 6. Phenylhydrazono-1,2,4-oxadiazoles have been reported to rearrange thermally into acylamino-1,2,3-triazoles. [12] Compound 5 could be obtained via refluxing 3 in DMF in the