Syntheses and medicinal chemistry of spiro heterocyclic steroids

• Laura L. Romero-Hernández,
• Ana Isabel Ahuja-Casarín,
• Penélope Merino-Montiel,
• Sara Montiel-Smith,
• José Luis Vega-Báez and
• Jesús Sandoval-Ramírez

Beilstein J. Org. Chem. 2024, 20, 1713–1745, doi:10.3762/bjoc.20.152

• -II) afforded the corresponding 17-spirolactams 123a,b in 71–73% yield (Scheme 34). Notably, when (S)-(+)-tert-butylsulfinamide was used in the initial step of the reaction sequence, the allylation of the resulting imine proceeded diastereoselectively, yielding the 17-allyl-17-sulfinamido compound as

• potentially favourable profile for prostate cancer therapy. Spirolactam steroids Steroidal spirolactams were obtained by Fousteris et al. in a five-step reaction sequence from 3β-benzyloxy-12β-hydroxydehydroepiandrosterone (118) [59]. The protected DHEA derivative was initially condensed with (R)-(+)-tert

• -butylsulfinamide, leading to the formation of the imine 119. Subsequent reaction with allylmagnesium bromide yielded a mixture of 17-allyl 17-sulfonamido derivatives 120a,b in a 2.5:1 diastereomeric ratio (17S:17R), which were isolated and treated separately. Acid treatment of the sulfinamides 120a,b resulted in

α-(Aminomethyl)acrylates as acceptors in radical–polar crossover 1,4-additions of dialkylzincs: insights into enolate formation and trapping

• Angel Palillero-Cisneros,
• Paola G. Gordillo-Guerra,
• Fernando García-Alvarez,
• Olivier Jackowski,
• Franck Ferreira,
• Fabrice Chemla,
• Joel L. Terán and
• Alejandro Perez-Luna

Beilstein J. Org. Chem. 2023, 19, 1443–1451, doi:10.3762/bjoc.19.103

•  5). Product (RS)-14b (85:15 dr), i.e., a mixture of two enantiomerically pure diastereomers, was obtained from (RS)-tert-butylsulfinamide upon allylation with tert-butyl α-(bromomethyl)acrylate followed by 1,4-addition with Et2Zn. It was then converted into the known β2-amino acid 17 by TFA-promoted

• informative. As discussed previously (Scheme 4), application of the developed protocol for 1,4-addition to 10 only yields N-benzyl-N-tert-butylsulfinamide following β-elimination. By contrast, in the presence of benzaldehyde, 1,4-addition–aldol condensation is predominant, yielding 26 in 56% yield as a 49:25

• of primary amines and tert-butylsulfinamide (preparation of compounds 5–7 and 8a–c). In a round-bottomed flask under argon, n-BuLi (1.0 equiv, soln. in heptane) was added dropwise to a THF (0.2 mol·L−1) solution of the appropriate primary amine or tert-butylsulfinamide (1.0 equiv) at −55 °C. The

N-tert-Butanesulfinyl imines in the asymmetric synthesis of nitrogen-containing heterocycles

• Joseane A. Mendes,
• Paulo R. R. Costa,
• Miguel Yus,
• Francisco Foubelo and
• Camilla D. Buarque

Beilstein J. Org. Chem. 2021, 17, 1096–1140, doi:10.3762/bjoc.17.86

• -benzyl-6,7-dimethoxy-N-methyl-1,2,3,4-tetrahydroisoquinoline (164), (−)-O,O-dimethylcoclaurine (165) and (+)-O-methylarmapavine (166) alkaloids via chiral tert-butylsulfinamide through a haloamide cyclization. The strategy was based on the addition of organomagnesium bromide or chloride to chiral N

Asymmetric synthesis of propargylamines as amino acid surrogates in peptidomimetics

• Matthias Wünsch,
• David Schröder,
• Tanja Fröhr,
• Lisa Teichmann,
• Sebastian Hedwig,
• Nils Janson,
• Clara Belu,
• Jasmin Simon,
• Shari Heidemeyer,
• Philipp Holtkamp,
• Jens Rudlof,
• Lennard Klemme,
• Alessa Hinzmann,
• Beate Neumann,
• Hans-Georg Stammler and
• Norbert Sewald

Beilstein J. Org. Chem. 2017, 13, 2428–2441, doi:10.3762/bjoc.13.240

• provided the desired 5-hydroxypentanenitrile and THF in the ratio 5:2 (monitored by 1H NMR spectroscopy, see Supporting Information File 1). Next, 4-cyanobutan-1-ol was oxidized in a Swern oxidation and the resulting aldehyde was condensed with tert-butylsulfinamide (S)-1, according to GP-2. The reaction

Synthesis of alkynyl-substituted camphor derivatives and their use in the preparation of paclitaxel-related compounds

• M. Fernanda N. N. Carvalho,
• Rudolf Herrmann and
• Gabriele Wagner

Beilstein J. Org. Chem. 2017, 13, 1230–1238, doi:10.3762/bjoc.13.122

• supported by the IR spectrum. Only one S=O vibration can be identified at 1098 cm−1, in a similar position as the S=O vibrations in DMSO (1050 cm−1) or tert-butylsulfinamide (1032 cm−1) [43]. The strong band at about 1330 cm−1, typical for the asymmetric S=O stretch in sulfonamides and sulfones, is absent

Thermal rearrangement of tert-butylsulfinamide

• Veera Reddy Arava,
• Laxminarasimhulu Gorentla and
• Pramod Kumar Dubey

Beilstein J. Org. Chem. 2011, 7, 9–12, doi:10.3762/bjoc.7.2

• above room temperature, and in chlorinated solvents they undergo rearrangement to form the more stable N-(tert-butylthio)-tert-butylsulfonamide. Keywords: chlorinated solvents; N-(tert-butylthio)-tert-butylsulfonamide; tert-butylsulfinamide; thermal rearrangement; Introduction Over the past decade, an

• ever increasing number of methods based upon the chiral amine reagent tert-butylsulfinamide (1) (Figure 1) has become one of the most extensively used synthetic approaches for both the production and discovery of drug candidates [1]. In particular, the tert-butylsulfinyl group showed high levels of

• room temperature and in chlorinated solvents. Experimental See Supporting Information File 1 for full experimental data. tert-Butylsulfinamide. N-(tert-butylthio)-tert-butylsulfonamide. ORTEP diagram of 3. Synthesis of acid amide. Chemical synthesis of 3. Synthesis of tert-butylsulfanyl chloride