Bicyclic molecule

About: Bicyclic molecule is a research topic. Over the lifetime, 29587 publications have been published within this topic receiving 451252 citations. The topic is also known as: bicyclic molecule.

1,3-Dipolar cycloaddition reactions of pyrazolidinium ylides with acetylenes. Synthesis of a new class of antibacterial agents

Abstract: Cycloadditions d'ylures de t-butoxycarbonylamino-4 alkylidene-1 oxo-3 pyrazolidiniums et de composes acetyleniques: synthese de t-butoxycarbonylamino-2 tetrahydro-1,2,3,5 pyrazolo [1,2-a] pyrazolones-1; acylation de ces composes sur l'amino-2 par le chlorure d'acide allyloxycarbonylamino-2 α-methoxyimino thiazoleacetique-4

1,6-Anhydro Derivatives of Aldohexoses

Abstract: Publisher Summary The 1,6-anhydroaldohexopyranoses and 1,6-anhydroaldohexofuranoses are aldohexose derivatives that can be formed from free hexoses by dehydration in such a way that intramolecular glycosides containing a glycosidically linked, primary hydroxyl group are formed. Depending on whether the D-hexose adopts the pyranoid or furanoid form, two analogous, bicyclic systems are formed—namely, 1,6-anhydro-β-D-aldohexopyranoses having a 6,8-dioxabicyclo[3.2.l]octane skeleton from the former, and 1,6-anhydro- β-D-aldohexofuranose having a 2,8-dioxabicyclo[3.2. l]octane skeleton from the latter. In their chemical properties, both these types of compound resemble to a certain degree the methyl β-D-aldopyranosides or the methyl α- or β-D-aldofuranosides. They do not have reducing properties, and are relatively stable in alkaline media, but are hydrolyzed by acids to the free hexoses. A characteristic feature of these compounds is their steric rigidity in the crystalline state as well as in solution. 1,6-anhydro-β-D-hexopyranoses are widely used in the synthesis of hexoses and their derivatives, oligosaccharides, and for polymerization to polysaccharides.

Five- and Six-Membered Conformationally Locked 2',4'-Carbocyclic ribo-Thymidines: Synthesis, Structure, and Biochemical Studies

Abstract: Two unusual reactions involving the 5-hexenyl or the 6-heptenyl radical cyclization of a distant double bond at C4‘ and the radical center at C2‘ of the ribofuranose ring of thymidine have been used as key steps to synthesize North-type conformationally constrained cis-fused bicyclic five-membered and six-membered carbocyclic analogues of LNA (carbocyclic-LNA-T) and ENA (carbocyclic-ENA-T) in high yields. Their structures have been confirmed unambiguously by long range 1H−13C NMR correlation (HMBC), TOCSY, COSY, and NOE experiments. The carbocyclic-LNA-T and carbocyclic-ENA-T were subsequently incorporated into the antisense oligonucleotides (AONs) to show that they enhance the Tm of the modified AON/RNA heteroduplexes by 3.5−5 °C and 1.5 °C/modification for carbocyclic-LNA-T and carbocyclic-ENA-T, respectively. Whereas the relative RNase H cleavage rates with carbocyclic-LNA-T, carbocyclic-ENA-T, aza-ENA-T, and LNA-T modified AON/RNA duplexes were found to be very similar to that of the native counterpar...

2- and 4-aminopyrimidines n-substtituded by a bicyclic ring for use as kinase inhibitors in the treatment of cancer

Abstract: A coumpound of the formula (I) wherein each X is independently NR1R6, NR4R5, or R4, with the proviso that at least one X must be NR1R6; each R1 is independently an optionally substituted fused bicyclic unsaturated ring containing 9 or 10 atoms optionally containing 1-4 heteroatoms selected from the group consisting of N, S and O, and the variables R2-6 are as defined in claim 1, are claimed. These compounds are kinase inhibitors useful in the treatment of cancer and viral infections.

Bicyclic fibrinogen antagonists

Abstract: This invention relates to compounds of formula (I), wherein A1 to A5 form an accessible substituted seven-membered ring, which may be saturated or unsaturated, optionally containing up to two heteroatoms chosen from the group of O, S and N wherein S and N may be optionally oxidized; D1 to D4 form an accessible substituted six membered ring, optionally containing up to two nitrogen atoms; R is at least one substituent chosen from the group of R7, or Q-C?1-4?alkyl, Q-C2-4alkenyl, Q-C2-4alkynyl, preferably substituted by an acidic function; R* is H, Q-C1-6alkyl, Q-C1-6oxoalkyl, Q-C2-6alkenyl or Q-C2-4alkynyl, C3-6cycloalkyl, Ar or Het, optionally substituted by one or more substituents; and R?6? is preferably a substituent containing a basic nitrogen moiety; or a pharmaceutically acceptable salt thereof, which are effective for inhibiting platelet aggregation, pharmaceutical compositions for effecting such activity, and a method for inhibiting platelet aggregation.