L- -piperazine

Barbital (diethylbarbituric acid, Veronal) HEPPS (EPPS. 4-(2-hydroxyethyl)-l-piperazin-propanesulfonic acid)... 

Nucleic acids catalyze many different types of reactions. Some RNA-catalyzed transformations show stereoselectivity [10,34]. The potential scope of organic reactions is quite broad, with a commensurate variability in reaction conditions. The essential components present in successful nucleic acid-catalyzed reactions are divalent metal ions such as Mg2+, Ca2+, Cu2+, Zn2+, as well as K+ [7,10,21,35,36]. A buffer is also required but should not contain functional groups that are reactive under the reaction conditions. A commonly used buffer is HEPES (2-[4-(2-hydroxyethyl)-l-piperazine]ethanesulfonic acid). These essential components are present to maintain the RNA s tertiary structure and prevent its aggregation. Because these reactions are carried out in aqueous solution, the addition of a co-solvent (e. g., DM SO or EtOH) may be necessary, depending on the solubility of the substrates. 

Chemical Name N,N-Diethyl-4-methyl-l-piperazine-carboxamide citrate... 

Chemical Name 4-[3-(5H-Dibenz[b,f]azepin-5-yl)propyl]-l-piperazine-ethanol... 

ADP adenosine diphosphate, ANP atrial natriuretic peptide, AP5DTPT(5 -adenosyl)P5-(5 -thymidyl)pentaphosphate, ATP adenosine triphosphate, AZTMP 3 -azido-3 -deoxythymidine monophosphate, dGMP deoxyguanosine monophosphate, P 4-(2-hydroxyethyl)-l-piperazine ethanesulfonic acid, HMD hymenialdisine, TMP thymidine monophosphate... 

Note It seems relevant that aqueous solutions of A -m e (h y I diethanolamine (77), employed to remove H2S from hydrocarbon gases, gradually accumulate inter alia 1,4-dimethyl-, l-(2-hydroxyethyl)-4-methyl-, and l,4-bis(2-hydrox-yethy l)piperazine.158 3... 

SYNS 8-(4-(4-CHLOROPHENYLPHENYLMETHYL)-PIPERAZINYL)-3,6-DIOXAOCTANOL 3,6-DIOXA-OCTANOL, 8-(4-(4-CHLOROPHENYLPHENYL-METHYL)PIPERAZINYL)- ETHANOL, 2-(2-(2-(4-(p-CHLORO-a-PHENYLBENZYL)-l-PIPERAZINYL)-ETHOXPETHOXY)- ETHANOL,- 2-(2-(2-(4-((4-CHLOROPHEN YL)PHENYLMETHYL)-l-PIPERAZIN-YL)ETHOXpETHOXY)- ETODROXINE ETODRO-XYZINE TOSPARAX-WIRKSTOFF UCB 1414... 

SYNS CHLORO-3 (N-METHYLPIPERAZINYL-3 PROPYL)-10 PHENOTHIAZINE (FRENCH) 2-CHLORO-10-(3-(l -METH YL-4-PIPERAZINYL)-PROPYL)-PHENOTHIAZINE 2-CHLORO-10-(3-(4-METHYL-l-PIPERAZIN YL)PROP YL)PHENOTHIAZINE 3-CHLORO-10-(3-(l-METHYL-4-PIPERAZINYL)PROPYL)-PHENOTHIAZINE CHLORPERAZINE COMPAZINE... 

SYNS BIFORMYCHLORAZIN BIFORMYLCHLO-RAZIN N,N -BIS(l-FORMAMIDO-2,2,2-TRICHLORO-ETHA L)PIPERAZINE l,4-BIS(l-FORMAMIDO-2,2,2-TRICHLOROETHYL)PIPERAZINE CA 70203 CELA 50 CELA W 524 CME 74770 COMPOUND W CW 524 FORMAAnDE,NJ4 -(l,4-PIPERAZINEDIYLBIS-(2,2,2-TRICHLOROETHYLIDENE))BIS-(8CI,9CI) FUNG-INEX N3SI -(PIPERAZINEDIYLBIS(2,2,2-TRICHL0R0-ETHYLIDENE)) BIS(FORMAMIDE) SAPROL W 524... 

In a search for new anti-cancer agents Abdel-Rahman (92FA319) (Scheme 3) obtained dipyrazol-3-one derivative 15 by heating two equivalents of 5-aminopyr-azol-3-one 13 with 2-chloro-l-(piperazin-l-yl)ethanone derivative 14 in DMF. 

Due to their high selectivity, DER and DEL were the basis for an extensive structure activity relationship study aimed to understand the essential requisites of p. and 8 activity. More than 200 analogues of DER and DEL C were synthesized, and the role of each amino acid in binding to p and 8 receptors and bioactivity was defined [21-31]. New synthetic products were prepared such as oxymorphindole and related derivatives [32], and (+)-4-[(alfa R)-alfa-((2S,5R)-4-allyl-2.5-dimethyl-l-piperazin-yl)-3-methoxy-benzyl]-N, diethylbenzamide [33]. These products are under investigation for their clinical relevance and provide potential nonpeptide ligands for studies on delta-opioid-receptor. 

The current state of the art involves the use of piperazine compounds which react with diisocyanates to form electrochemically detectable or fluorescent urea derivatives (Eickeler, 1990 Warwick et al., 1981 Schmidtke and Seifert, 1990 Brown et al., 1987 Bagon et al., 1984 Ellwood et al., 1981). Two OSHA methods (nos. 42 and 47) (OSHA, 1989a OSHA, 1989h) describe a derivatization with l-(2-pyridyl)-piper-azine (2PP) to l,6-bis-[4-(2-pyridyl)-l-piperazine-carbamyl]-hexane (HDI-2PP), 2,6-bis-[4-(2-pyridyl)-1 -piperazine-carbamyl]-toluene (2,6-TDI-2PP), 2,4-bis-[4-(2-pyri-dyl)-l-piperazine-carbamyl]-toluene (2,4-TDI-2PP) and N,N -(methylenedipheny-lene)-bis-4-(2-pyridinyl)-l-piperazine-carboxamide (MDI-2PP) on a coated filter, using the combination HPLC/fluorescence for separation and detection, respectively. 

A second crop is a also collected from the ensuing filtrate. This product is dissolved in 200 ml chloroform and treated with an excess of anhydrous hydrogen chloride (gas). The precipitate thus obtained is collected and dried at 50°C (in vacuo). It is the penultimate intermediate called 4-methyl-2 -(pam-chlorophenoxy-l-piperazine carhoxanilide hydrochloride (II) having mp 210-213 C. 

HT2A ligands derived from trans-l-piperazines-3-phenylindans... 

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