Convergent syntheses of Le^X analogues

• An Wang,
• Jenifer Hendel and
• France-Isabelle Auzanneau

Beilstein J. Org. Chem. 2010, 6, No. 17, doi:10.3762/bjoc.6.17

• isolated in excellent yield whether method A or B was followed. Thus, these syntheses of glycoside 14 constitute efficient alternatives to that reported by Nitz et al. in which the starting material was the corresponding anomeric bromide [45]. Nucleophilic displacement of the chlorine atom in glycoside 14

• glycoside 29 was in turn used as a precursor to the 6-azidohexyl, 6-acetylthiohexyl and 6-thiobenzylhexyl trisaccharides 30–32 (Scheme 3). Thus, nucleophilic displacement of the chloride with sodium azide or potassium thioacetate was carried out in DMF at 80 °C and provided the 6-azidohexyl and 6

Mitomycins syntheses: a recent update

• Jean-Christophe Andrez

Beilstein J. Org. Chem. 2009, 5, No. 33, doi:10.3762/bjoc.5.33

• leaving group X free for nucleophilic displacement with the nitrogen of the newly formed pyrroline. The synthesis began by Mitsunobu coupling of phenol 76 with allylic alcohol 77 to give ether 78, which was heated in N,N-dimethylaniline to trigger a Claisen rearrangement (Scheme 22). A sequence of

Synthesis of crispine A analogues via an intramolecular Schmidt reaction

• Ajoy Kapat,
• Ponminor Senthil Kumar and
• Sundarababu Baskaran

Beilstein J. Org. Chem. 2007, 3, No. 49, doi:10.1186/1860-5397-3-49

• as a white crystalline solid. Diol 9 on bromination followed by nucleophilic displacement with NaCN furnished the desired dicyano compound 10. Treatment of dicyanide 10 with thionyl chloride in methanol gave the corresponding diester 11 as a colorless liquid in good yield. Compound 11 was then

Aroylketene dithioacetal chemistry: facile synthesis of 4-aroyl- 3-methylsulfanyl- 2-tosylpyrroles from aroylketene dithioacetals and TosMIC

• H. Surya Prakash Rao and
• S. Sivakumar

Beilstein J. Org. Chem. 2007, 3, No. 31, doi:10.1186/1860-5397-3-31

• . Future works will concentration on desulfuration of the methylsulfanyl group in 3 to generate 3,5-disubstituted pyrroles or oxidation of methylsulfanyl group to methylsulfonyl group followed by nucleophilic displacement to generate pyrroles of structural diversity. Experimental "See the Supporting

Efficient synthesis of 5-substituted 2-aryl- 6-cyanoindolizines via nucleophilic substitution reactions

• Eugene V. Babaev,
• Natalya I. Vasilevich and
• Anna S. Ivushkina

Beilstein J. Org. Chem. 2005, 1, No. 9, doi:10.1186/1860-5397-1-9

• synthesis of previously unknown 5-chloroindolizines and their use as precursors to novel 5-substituted indolizines via nucleophilic displacement reactions. The synthesis of 2-aryl-5-chloro-6-cyano-7-methylindolizines 2 is shown in Scheme 1. 2-Aryl-6-cyano-7-methyl-5-indolizinones 1 a – d were prepared

Synthesis of 2,6-trans- disubstituted 5,6-dihydropyrans from (Z)-1,5-syn-endiols

• Eric M. Flamme and
• William R. Roush

Beilstein J. Org. Chem. 2005, 1, No. 7, doi:10.1186/1860-5397-1-7

• silylation of the allylic alcohol unit followed by mesylate formation and base-promoted nucleophilic displacement. Findings We recently reported a one-pot double allylboration reaction sequence which provides (Z)-1,5-syn-endiols from simple aldehyde starting materials with excellent diastereo- and