stereoisomers

Metolachlor 是出苗前的选择性的，氯乙酰苯胺除草剂，由四种立体异构体组成的手性除草剂。它可用于控制玉米和其他农作物中的各种一年生草和阔叶杂草。

CP 65207 is a new broad-spectrum penicillin antibacterial agent, which is a mixture of two stereoisomers (1:1).

Neo-Inositol is a group of chemically very stable small polar molecules with a variety of properties. It is one of the naturally occurring but rare inositol stereoisomers.

19-HETE is one of the major cytochrome P450 (CYP450) metabolites of arachidonic acid that is released from the kidney in response to angiotensin II. When formed by the CYP2E1 isoform, 19-HETE is composed of 70% and 30% of the (S) and (R) stereoisomers, respectively. Both 19(S)- and 19(R)-HETE are potent vasodilators of renal preglomerular vessels. 19(S)-HETE stimulates both renal sodium-potassium ATPase and volume absorption in the rabbit proximal straight tubule.

PDMP is a ceramide analog first prepared in a search for inhibitors of glucosylceramide synthase. PDMP has two adjacent chiral centers (C1 and C2) allowing for the formation of four possible isomers. PDMP contains all four of these stereoisomers. PDMP inhibits glucosylceramide synthase by 90% when used at a concentration of 0.8 μM in MDCK cell homogenates, however, the ability to inhibit glucosylceramide synthase has been found to reside in the D-threo (1R,2R) enantiomer. The D-threo PDMP enantiomer is also responsible for inhibition of β-1,4-galactosyltransferase 6 and prevention of lactosylceramide synthesis, which is a promotor of neuroinflammation in mice during chronic experimental autoimmune encephalomyelitis (EAE), a model of multiple sclerosis. PDMP enhances curcumin-induced inhibition of proliferation, JNK activation, and Akt inhibition, as well as induction of apoptosis in WM-115 melanoma cells in vitro.

Iloprost is a second generation structural analog of prostacyclin (PGI2) with about ten-fold greater potency than the first generation stable analogs, typified by carbaprostacyclin. Iloprost binds with equal affinity to the recombinant human IP and EP1 receptors with a Ki value of 11 nM. Most preparations of iloprost contain 16(S) and 16(R) stereoisomers. 16(R)-Iloprost inhibits platelet aggregation with an IC50 value of 65 nM.

Iloprost is a second generation structural analog of prostacyclin (PGI2) with about ten-fold greater potency than the first generation stable analogs, typified by carbaprostacyclin. Iloprost binds with equal affinity to the recombinant human IP and EP1 receptors with a Ki value of 11 nM. Most preparations of iloprost contain 16(S) and 16(R) stereoisomers. 16(S)-Iloprost potently inhibits platelet aggregation with an IC50 value of 3.5 nM.

Novel oxylipins, referred to as docosanoids, have been derived from C22polyunsaturated fatty acids 7(S),17(S)-dihydroxy-8(E),10(Z),13(Z),15(E),19(Z)-Docosapentaenoic acid (7(S),17(S)-hydroxy DPA) is a DPA-derived analog of the 17(S)-dihydroxy series of docosanoids known as protectins. Protectin D1, a DHA-derived dihydroxy fatty acid, exhibits potent anti-inflammatory activities.1,2,3Potentially, 7(S),17(S)-hydroxy DPA demonstrates similar properties; however, its biological activity has yet to be determined. 1.Serhan, C.N., Gotlinger, K., Hong, S., et al.Anti-inflammatory actions of neuroprotectin D1 protectin D1 and its natural stereoisomers: Assignments of dihydroxy-containing docosatrienesJ. Immunol.176(3)1848-1859(2006) 2.Ariel, A., and Serhan, C.N.Resolvins and protectins in the termination program of acute inflammationTRENDS in Immunology28(4)176-183(2007) 3.Schwab, J.M., Chiang, N., Arita, M., et al.Resolvin E1 and protectin D1 activate inflammation-resolution programmesNature447(7146)869-874(2007)

(+)-D-threo-PDMP is a ceramide analog and is one of the four possible stereoisomers of PDMP . (+)-D-threo-PDMP is an inhibitor of glucosylceramide synthase. It inhibits glucosylceramide synthase by 50% when used at a concentration of 5 μM in an enzyme assay. (+)-D-threo-PDMP is the active component of racemic DL-threo-PDMP .

D-DOPA is an enantiomer of the dopamine precursor L-DOPA . It can be converted to L-DOPAviasequential oxidation and transamination, which are mediated by D-amino acid oxidase (DAAO) and DOPA transaminase, respectively, in rat kidney homogenates.1It reduces the number of dopaminergic neurons in primary rat embryonic mesencephalic cultures in a concentration-dependent manner.2Intraventricular administration of D-DOPA (200 μg/animal) increases striatal dopamine levels in rats.3D-DOPA (20 mg/kg, i.p.) induces contralateral turns in a rat model of Parkinson's disease induced by 6-OHDA .4 1.Wu, M., Zhou, X.-J., Konno, R., et al.D-dopa is unidirectionally converted to L-dopa by D-amino acid oxidase, followed by dopa transaminaseClin. Exp. Pharmacol. Physiol.33(11)1042-1046(2006) 2.Ling, Z.-D., Pieri, S.C., and Carvey, P.M.Comparison of the neurotoxicity of dihydroxyphenylalanine stereoisomers in cultured dopamine neuronsClin. Neuropharmacol.19(4)360-365(1996) 3.Karoum, F., Freed, W.J., Chuang, L.-W., et al.D-dopa and L-dopa similarly elevate brain dopamine and produce turning behavior in ratsBrain Res.440(1)190-194(1988) 4.Moses, J., Siddiqui, A., and Silverman, P.B.Sodium benzoate differentially blocks circling induced by D-and L-dopa in the hemi-parkinsonian ratNeurosci. Lett.218(3)145-148(1996)

Sphingosines are long-chain base precursors of cellular sphingolipids used directly in the synthesis of ceramide, which in combination with sialic acid forms ganglioside. Sphingosine can exist in four stereoisomers, however only sphingosine occurs naturally. Compared to other sphingolipids throughout the body, which are predominantly composed of C-18 sphingosine, only central nervous system (CNS) gangliosides contain significant amounts of sphingosine. The concentration of sphingosine within mammalian brain gangliosides apparently increases with developmental maturation. Furthermore, the ratio of C-18 to C-20 sphingosine in the brain is thought to be related to some nervous system degeneration processes.

Hodgkinsine B is an alkaloid and isomer of hodgkinsine that has analgesic activity.1It increases the latency to tail withdrawal in the tail-flick test in mice when administered at a dose of 10 mg kg. 1.Kodanko, J.J., Hiebert, S., Peterson, E.A., et al.Synthesis of all low-energy stereoisomers of the tris(pyrrolidinoindoline) alkaloid hodgkinsine and preliminary assessment of their antinociceptive activityJ. Org. Chem.72(21)7909-7914(2007)

Scyllo-Inositol (Scyllitol) 是淀粉样抑制剂，能够抑制 α-突触核蛋白聚集。它在体外能够稳定非纤维状无毒形式的淀粉样蛋白-β 肽，逆转阿尔茨海默病小鼠模型的认知缺陷，抑制突触毒性和淀粉样斑块。

20(S),24(R)-Ocotillol, a natural product, is characterized by a unique structure featuring specific stereoisomers denoted by (S) at carbon 20 and (R) at carbon 24.