Category: piperidines

On April 15, 2004, Duan, Jingwu; King, Bryan W.; Decicco, Carl; Maduskuie, Thomas P.; Voss, Mathew E. published a patent.Electric Literature of 362703-57-9 The title of the patent was Preparation of β-amino acid derivatives as inhibitors of matrix metalloproteases and TNF-α. And the patent contained the following:

Novel β-amino acid derivatives A-CR3R4aCR2R4NR1CO-X-Z-Ua-Xa-Ya-Za [A = CO2H, SH, CH2SH, S(O)Ra:NH (Ra = H, alkyl), P(O)(OH)2, etc.; X, Xa is absent or alkylene, alkenylene or alkynylene; Z is absent or substituted C3-13 carbocycle or 5-14 membered heterocycle; Ua is absent or O, NRa1 [Ra1 = H, (un)substituted alkyl, alkenyl or alkynyl; Ra and Ra1 may form a ring], CO, CO2, O2C, CONRa1, S(O)p (p = 0-2), etc.; Ya is absent or O, NRa1, S(O)p or CO; Za is H, substituted C3-13 carbocycle or 5-14 membered heterocycle; R1 is H, alkyl, Ph, benzyl; R2 is Q (Q is H, substituted carbocycle or heterocycle), alkylene-Q, (CRaRa1)r1O(CRaRa1)r-Q (r, r1 = 0-4), (CRaRa1)r1NRa(CRaRa1)r-Q, etc.; R3 = Q1 (Q1 is any group given for Q), alkylene-Q1, (CRaRa1)r1O(CRaRa1)r-Q1, (CRaRa1)r1NRa(CRaRa1)r-Q1, etc.; R4, R4a = H, substituted alkyl, alkenyl or alkynyl; alternatively R1 and R2, R1 and R3, R3 and R4a may form rings (with provisos)] or a stereoisomer or pharmaceutically acceptable salt were prepared as metalloprotease and TNF-α inhibitors. Thus, N-hydroxy-1-[[4-[(2-methyl-4-quinolinyl)methoxy]phenyl]acetyl]-3-azetidinecarboxamide was prepared by a multistep procedure involving reactions of Me 4-hydroxyphenylacetate, 2-methyl-4-quinolinylmethanol, and 3-azetidinecarboxylic acid Me ester. The experimental process involved the reaction of tert-Butyl 4-amino-4-(2-methoxy-2-oxoethyl)piperidine-1-carboxylate(cas: 362703-57-9).Electric Literature of 362703-57-9

The Article related to amino acid beta preparation inhibitor metalloprotease tnf, heterocyclyl beta amino acid preparation inhibitor metalloprotease tnf, cycloalkyl beta amino acid preparation inhibitor metalloprotease tnf and other aspects.Electric Literature of 362703-57-9

Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem

On September 27, 2001, Duan, Jingwu; King, Bryan W.; Decicco, Carl; Maduskuie, Thomas P., Jr.; Voss, Matthew E. published a patent.Electric Literature of 362703-57-9 The title of the patent was Preparation of β-amino acid derivatives as inhibitors of matrix metalloproteases and TNF-α. And the patent contained the following:

Novel β-amino acid derivatives A-CR3R4aCR2R4NR1CO-X-Z-Ua-Xa-Ya-Za [A = CO2H, SH, CH2SH, S(O)Ra:NH (Ra = H, alkyl), P(O)(OH)2, etc.; X, Xa is absent or alkylene, alkenylene or alkynylene; Z is absent or substituted C3-13 carbocycle or 5-14 membered heterocycle; Ua is absent or O, NRa1 [Ra1 = H, (un)substituted alkyl, alkenyl or alkynyl; Ra and Ra1 may form a ring], CO, CO2, O2C, CONRa1, S(O)p (p = 0-2), etc.; Ya is absent or O, NRa1, S(O)p or CO; Za is H, substituted C3-13 carbocycle or 5-14 membered heterocycle; R1 is H, alkyl, Ph, benzyl; R2 is Q (Q is H, substituted carbocycle or heterocycle), alkylene-Q, (CRaRa1)r1O(CRaRa1)r-Q (r, r1 = 0-4), (CRaRa1)r1NRa(CRaRa1)r-Q, etc.; R3 = Q1 (Q1 is any group given for Q), alkylene-Q1, (CRaRa1)r1O(CRaRa1)r-Q1, (CRaRa1)r1NRa(CRaRa1)r-Q1, etc.; R4, R4a = H, substituted alkyl, alkenyl or alkynyl; alternatively R1 and R2, R1 and R3, R3 and R4a may form rings (with provisos)] or a stereoisomer or pharmaceutically acceptable salt were prepared as metalloprotease and TNF-α inhibitors. Thus, N-hydroxy-1-[[4-[(2-methyl-4-quinolinyl)methoxy]phenyl]acetyl]-3-azetidinecarboxamide was prepared by a multistep procedure involving reactions of Me 4-hydroxyphenylacetate, 2-methyl-4-quinolinylmethanol, and 3-azetidinecarboxylic acid Me ester. The experimental process involved the reaction of tert-Butyl 4-amino-4-(2-methoxy-2-oxoethyl)piperidine-1-carboxylate(cas: 362703-57-9).Electric Literature of 362703-57-9

The Article related to amino acid beta preparation inhibitor metalloprotease tnf, heterocyclyl beta amino acid preparation inhibitor metalloprotease tnf, cycloalkyl beta amino acid preparation inhibitor metalloprotease tnf and other aspects.Electric Literature of 362703-57-9

Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem

On April 27, 2006, Burgey, Christopher S.; Paone, Daniel V.; Shaw, Anthony W.; Nguyen, Diem N.; Deng, Zhengwu J.; Williams, Theresa M.; Vacca, Joseph P.; Selnick, Harold G.; Potteiger, Craig M. published a patent.Quality Control of Benzyl 7′-chloro-2′-oxo-1′,2′-dihydrospiro[piperidine-4,4′-pyrido[2,3-d][1,3]oxazine]-1-carboxylate The title of the patent was Imidazolo[1,2-a]azepane and triazolo[4,3-a]azepane derivatives as CGRP receptor antagonists and their preparation, pharmaceutical compositions, and use for treatment of diseases in which CGRP is involved such as headache, migraine and cluster headache. And the patent contained the following:

Compounds of formula I and formula II are useful as antagonists of CGRP receptors and useful in the treatment or prevention of diseases in which the CGRP is involved, such as headache, migraine and cluster headache. The invention is also directed to pharmaceutical compositions comprising these compounds and the use of these compounds and compositions in the prevention or treatment of such diseases in which CGRP is involved. Compounds of formula I and II wherein Z is (un)substituted piperidine or (un)substituted spiropiperidine; A is C(R2)2, O, SOm, or NR2; B is [C(R2)2]n; D is N or CR1; R1 is H, (un)substituted C1-6 alkyl, (un)substituted C2-6 alkenyl, (un)substituted C2-6 alkynyl, (un)substituted C3-6 cycloalkyl, (un)substituted heterocyclyl, or (un)substituted (hetero)aryl; each R2 is independently H, (un)substituted C0-6 alkyl, (un)substituted C2-6 alkenyl, (un)substituted C2-6 alkynyl, (un)substituted C3-6 cycloalkyl, (un)substituted heterocyclyl, (un)substituted (hetero)aryl; any two R2 on the same or adjacent atoms optionally join to form cycloalkyl, (hetero)aryl, or heterocycloalkyl ring; W is O, NR4 or C(R4)2; R4 is H, (un)substituted (fluoro)C1-6 alkyl, (un)substituted C3-6 cycloalkyl, and (un)substituted (hetero)aryl, or benzyl; X is C or S; Y is O, (R4)2, NCN, NSO2Me or NCONH2; or Y is O2 when X is S; m is O, 1, or 2; n is 1 or 2; and pharmaceutically acceptable salts and diastereoisomers thereof are claimed in this invention. Example compound III was prepared by condensation of N-[(3R,6S)-6-(2,3-difluorophenyl)-2-thioxoazepan-3-yl]-4-(2-oxo-2,3-dihydro-1H-imidazo[4,5-b]pyridin-1-yl)piperidine-1-carboxamide with 1-amino-3-methylbutan-2-ol to give N-[(3R,6S)-6-(2,3-difluorophenyl)-2-[(2-hydroxy-3-methylbutyl)imino]azepan-3-yl]-4-(2-oxo-2,3-dihydro-1H-imidazo[4,5-b]pyridin-1-yl)piperidine-1-carboxamide TFA salt, which underwent oxidation to give example compound III. All the invention compounds were evaluated for their activity as antagonists of the CGRP receptor. From the assay, the example compounds, in general, exhibited Ki or IC50 values of less than about 50 μM. The experimental process involved the reaction of Benzyl 7′-chloro-2′-oxo-1′,2′-dihydrospiro[piperidine-4,4′-pyrido[2,3-d][1,3]oxazine]-1-carboxylate(cas: 883984-95-0).Quality Control of Benzyl 7′-chloro-2′-oxo-1′,2′-dihydrospiro[piperidine-4,4′-pyrido[2,3-d][1,3]oxazine]-1-carboxylate

The Article related to imidazoloazepane triazoloazepane preparation pharmaceutical composition cgrp receptor antagonist, triazoloazepane imidazoloazepane preparation treatment headache migraine cgrp receptor antagonist and other aspects.Quality Control of Benzyl 7′-chloro-2′-oxo-1′,2′-dihydrospiro[piperidine-4,4′-pyrido[2,3-d][1,3]oxazine]-1-carboxylate

Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem

Reference of TriacetonamineOn September 1, 2021 ,《Catalytic ozonation for metoprolol and ibuprofen removal over different MnO2 nanocrystals: Efficiency, transformation and mechanism》 was published in Science of the Total Environment. The article was written by He, Yuan; Wang, Liangjie; Chen, Zhan; Shen, Bo; Wei, Jinshan; Zeng, Ping; Wen, Xianghua. The article contains the following contents:

Manganese dioxide has been widely recognized as catalyst in catalytic ozonation for organic pollutants removal from wastewater in recent decades. However, few studies focus on the structure-activity relationship of MnO2 and catalytic ozonation mechanism in water. In the present study, the oxidative reactivity of three different crystal phases of MnO2 corresponding to α-MnO2, β-MnO2 and γ-MnO2 towards metoprolol (MET) and ibuprofen (IBU) were evaluated. α-MnO2 was found to contain the most abundant oxygen vacancy and readily reducible surface adsorbed oxygen (O2-, O-, OH-), which facilitated an increase of ozone utilization and the highest catalytic performance with 99% degradation efficiency for IBU and MET. α-MnO2 was then selected to investigate the optimum key operating parameters with a result of catalyst dosage 0.1 g/L, ozone dosage 1 mg/min and an initial pH 7. The introduction of α-MnO2 promoted reactive oxygen species (O2-, O-, OH-) generation which played significant roles in IBU degradation Probable degradation pathways of MET and IBU were proposed according to the organic intermediates identified and the reaction sites based on d. function theory (DFT) calculations The present study deepened our understanding on the MnO2 catalyzed ozonation and provided reference to enhance the process efficiency. The experimental part of the paper was very detailed, including the reaction process of Triacetonamine(cas: 826-36-8Reference of Triacetonamine)

Triacetonamine(cas: 826-36-8) is a member of piperidine. Piperidine-containing compounds are also frequently employed in synthesis as ligands or auxiliaries. Accordingly, many efforts have been devoted to the development of novel methods for the synthesis of these compounds over the years.Reference of Triacetonamine

Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem

HPLC of Formula: 39546-32-2On September 9, 2019 ,《One-Pot Parallel Synthesis of 5-(Dialkylamino)tetrazoles》 was published in ACS Combinatorial Science. The article was written by Savych, Olena; Kuchkovska, Yuliya O.; Bogolyubsky, Andrey V.; Konovets, Anzhelika I.; Gubina, Kateryna E.; Pipko, Sergey E.; Zhemera, Anton V.; Grishchenko, Alexander V.; Khomenko, Dmytro N.; Brovarets, Volodymyr S.; Doroschuk, Roman; Moroz, Yurii S.; Grygorenko, Oleksandr O.. The article contains the following contents:

Two protocols for the combinatorial synthesis of 5-(dialkylamino)tetrazoles were developed. The best success rate (67%) was shown by the method that used primary and secondary amines, 2,2,2-trifluoroethylthiocarbamate, and sodium azide as the starting reagents. The key steps included the formation of unsym. thiourea, subsequent alkylation with 1,3-propane sultone and cyclization with azide anion. A 559-member aminotetrazole library was synthesized by this approach; the overall readily accessible (REAL) chem. space covered by the method exceeded 7 million feasible compounds The results came from multiple reactions, including the reaction of Piperidine-4-carboxamide(cas: 39546-32-2HPLC of Formula: 39546-32-2)

Piperidine-4-carboxamide(cas: 39546-32-2) belongs to anime.Typically the presence of an amine functional group is deduced by a combination of techniques, including mass spectrometry as well as NMR and IR spectroscopies. 1H NMR signals for amines disappear upon treatment of the sample with D2O. In their infrared spectrum primary amines exhibit two N-H bands, whereas secondary amines exhibit only one.HPLC of Formula: 39546-32-2

Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem

Application In Synthesis of (S)-1-tert-Butyl 2-ethyl 4-oxopiperidine-1,2-dicarboxylateOn June 10, 1996, Machetti, Fabrizio; Cordero, Franca M.; De Sarlo, Francesco; Guarna, Antonio; Brandi, Alberto published an article in Tetrahedron Letters. The article was 《Rearrangement of isoxazolidine 5-spiro derivates. 13. A new synthesis of (2S)-4-oxopipecolic acid by thermal rearrangement of enantiopure spirocyclopropaneisoxazolidine》. The article mentions the following:

A novel synthesis of (2S)-4-oxopipecolic acid is reported. The synthetic route employs as a key step the diastereoselective cycloaddition of the N-glycosylnitrone I to methylenecyclopropane followed by thermal rearrangement of the spirocyclopropaneisoxazolidine II. Stereoselective reduction of the N-Boc 4-oxopipecolic acid Et ester by L-selectride gives the protected cis-4-hydroxypipecolic acid III. The experimental part of the paper was very detailed, including the reaction process of (S)-1-tert-Butyl 2-ethyl 4-oxopiperidine-1,2-dicarboxylate(cas: 180854-44-8Application In Synthesis of (S)-1-tert-Butyl 2-ethyl 4-oxopiperidine-1,2-dicarboxylate)

(S)-1-tert-Butyl 2-ethyl 4-oxopiperidine-1,2-dicarboxylate(cas: 180854-44-8) is a member of piperidine. Piperidine is a key saturated heterocyclic scaffold found in several of the top-selling small molecule pharmaceuticals and natural alkaloids, with a diverse range of biological activities. Hence, continuous efforts have been made to develop convenient methods to prepare piperidine derivatives.Application In Synthesis of (S)-1-tert-Butyl 2-ethyl 4-oxopiperidine-1,2-dicarboxylate

Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem

Recommanded Product: 2-(Piperidin-4-yl)ethanolIn 2012 ,《Discovery of (2S)-1-[4-(2-{6-Amino-8-[(6-bromo-1,3-benzodioxol-5-yl)sulfanyl]-9H-purin-9-yl}ethyl)piperidin-1-yl]-2-hydroxypropan-1-one (MPC-3100), a Purine-Based Hsp90 Inhibitor》 appeared in Journal of Medicinal Chemistry. The author of the article were Kim, Se-Ho; Bajji, Ashok; Tangallapally, Rajendra; Markovitz, Benjamin; Trovato, Richard; Shenderovich, Mark; Baichwal, Vijay; Bartel, Paul; Cimbora, Daniel; McKinnon, Rena; Robinson, Rosann; Papac, Damon; Wettstein, Daniel; Carlson, Robert; Yager, Kraig M.. The article conveys some information:

Modulation of Hsp90 (heat shock protein 90) function has been recognized as an attractive approach for cancer treatment, since many cancer cells depend on Hsp90 to maintain cellular homeostasis. This has spurred the search for small-mol. Hsp90 inhibitors. Here we describe our lead optimization studies centered on the purine-based Hsp90 inhibitor 28a (I; R = CHO) containing a piperidine moiety at the purine N9 position. In this study, key SAR was established for the piperidine N-substituent and for the congeners of the 1,3-benzodioxole at C8. These efforts led to the identification of orally bioavailable 28g [I; R = (S)-2-hydroxypropanoyl] that exhibits good in vitro profiles and a characteristic mol. biomarker signature of Hsp90 inhibition both in vitro and in vivo. Favorable pharmacokinetic properties along with significant antitumor effects in multiple human cancer xenograft models led to the selection of 28g (MPC-3100) as a clin. candidate. The experimental part of the paper was very detailed, including the reaction process of 2-(Piperidin-4-yl)ethanol(cas: 622-26-4Recommanded Product: 2-(Piperidin-4-yl)ethanol)

2-(Piperidin-4-yl)ethanol(cas: 622-26-4) have been used as an intermediate in the synthetic preparation of cellular-active allosteric inhibitors of FAKRecommanded Product: 2-(Piperidin-4-yl)ethanol

Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem

SDS of cas: 622-26-4In 2019 ,《Fluorophenols bearing nitrogenated heterocycle moieties, a class of novel Keap1-Nrf2 protein-protein interaction inhibitors: synthesis, antioxidant stress screening and molecular docking》 appeared in Medicinal Chemistry Research. The author of the article were Feng, Xiu E.; Kong, De Peng; Ban, Shu Rong; Ge, Rui; Li, Qing Shan. The article conveys some information:

In the present study, we introduced the nitrogenated heterocycles and fluorine atoms into the 2,5′-dibromo-4,5,2′-trihydroxyl diphenylmethanone (LM49), a bromophenol analog previously reported for its strong antioxidant ability involving in the Keap1-Nrf2 pathway. Twenty-seven fluorophenols 6a-6g, 8a-8k, 10a-10g, and 12a-12b were prepared, evaluated for their antioxidant activity in EA.hy926 cells, and investigated their interacted approach and probable mode of action with key protein Keap1 by mol. docking. Fluorophenols 6f, 8d, 8f, 8h, and 8i with EC50 values ranging from 0.82 to 6.71 μM were found to be more active compared with the standard control quercetin (EC50 = 18 μM). Among them, compound 8h with an EC50 value of 0.82 μM showed the identical activity to lead compound LM49 (EC50 = 0.7 μM). Moreover, the preferable water solubility and forming salt possibility of 8h contribute to its druggability. Further mol. docking of the optimal compound 8h with key protein Keap1 indicated that 8h stably bonded to the receptor protein by the formation of hydrogen bonds, the conjugated six-membered ring was close to the key residue Arg-415 attached to the Nrf2 on Keap1-Kelch, affecting its properties, and the change leaded to the dissociation of Nrf2 from the junction with Keap1-Kelch into the nucleus exerting its antioxidant protective effect. This study introduced a class of fluorophenols containing nitrogenated heterocycles for the development of novel Keap1-Nrf2 protein-protein interaction (PPI) inhibitors. Keap1-Kelch is suggested the most potential target protein for such class of halophenols. After reading the article, we found that the author used 2-(Piperidin-4-yl)ethanol(cas: 622-26-4SDS of cas: 622-26-4)

2-(Piperidin-4-yl)ethanol(cas: 622-26-4) have been used as an intermediate in the synthetic preparation of cellular-active allosteric inhibitors of FAKSDS of cas: 622-26-4

Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem

Name: 1-Methyl-4-piperidoneIn 2020 ,《Chemically stable poly(meta-terphenyl piperidinium) with highly conductive side chain for alkaline fuel cell membranes》 appeared in Journal of Membrane Science. The author of the article were Lu, Chuanrui; Long, Chuan; Li, Yunxi; Li, Ziming; Zhu, Hong. The article conveys some information:

Poly(arylene piperidine)s (PAPs) backbones, which do not contain unstable ether bonds, was synthesized by one-pot, metal-free superacid-catalyzed polymerization for anion exchange membranes (AEMs) preparation Meta-terphenyl as a monomer of polymer to regulate the morphol. and properties of AEM was also used due to its spatially torsional configuration instead of the recently reported linear structure of meta-terphenyl. Long flexible hydrophilic chains were grafted onto poly(meta terphenyl piperidinium) (m-PTP) backbone to form four cationic functionalized side chains, promoting efficient transfer of OH- and optimizing the hydrophilic/hydrophobic microphase separation structure. The resulting AEM shows a high ion conductivity of 164 mS/cm (m-PTP-TFPE-21) at 80°C. Furthermore, stable piperidine cation and long alkyl spacer chain contributed to the excellent alkali stability of m-PTP-TFPE-TQA membrane which shows only 11.67% and 12.73% degradation in ion conductivity and IEC, resp., after soaking in 2 M NaOH at 80°C for 1500 h. The peak power d. of the H2/O2 single cell using m-PTP-TFPE-14 is 269 mW/cm2 at a c.d. of 540 mA/cm2 at 80°C. The results came from multiple reactions, including the reaction of 1-Methyl-4-piperidone(cas: 1445-73-4Name: 1-Methyl-4-piperidone)

1-Methyl-4-piperidone(cas: 1445-73-4) is a member of piperidine. Piperidine is ubiquitous structural motif widely occurred in diverse synthetically and naturally occurring bioactive molecules. Piperidines are an immensely important class of compounds medicinally: the piperidine ring is the most common heterocyclic subunit among FDA approved drugs.Name: 1-Methyl-4-piperidone

Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem

In 2022,Yang, Lincan; Wang, Zhiqian; Wang, Fanghui; Wang, Zhongming; Zhu, Hong published an article in Journal of Membrane Science. The title of the article was 《Poly(aryl piperidinium) anion exchange membranes with cationic extender sidechain for fuel cells》.Electric Literature of C6H11NO The author mentioned the following in the article:

Anion-exchange membrane fuel cells (AEMFCs) is a promising solution to decrease the cost of fuel cell, because it is adaptable to non-noble-metals catalysts and low-cost stack components. However, anion exchange membranes (AEMs), a crucial component of AEMFCs devices, with desired properties (high ions conductivity, excellent chem. stability, robust mech. strength, etc.) are currently unavailable. In this paper, poly(biphenyl N-methylpiperidine) (PBP) was synthesized as the backbones of AEMs, which could provide good chem. stability and robust mech. strength. Quaternary ammonium cations containing various types of substituent sidechains, including hydrophobic alkyl chain, hydrophilic PEG chain and multi-PEG chains, were introduced onto the PBP backbones, and resulting AEMs were named PBP-alkyl, PBP-PEG and PBP-TPEG, resp. The relationship between AEMs structure and performance were studied, and mol. dynamics (MD) simulations were carried out to microcosmically reveal the mechanism of structure-activity relationship. All the PBP-based AEMs have acceptable alk. stability and performance loss is less than 10% under 2 M NaOH at 80 °C for about 500 h. PBP-PEG has the highest ions conductivity of 97.3 mS cm-1 and lowest water uptake (WU), while PBP-TPEG has the lowest ions conductivity of 56.1 mS cm-1 and highest WU. For single cell evaluations at 80 °C under H2/O2 condition, AEMFC containing PBP-PEG membrane bursts out a highest peak power d. of 373 mW cm2, while PBP-alkyl and PBP-TPEG only achieve 133 and 93 mW cm-2, resp. MD results show the water channel of PBP-PEG is denser and more continuous than other structures, and the proportion of completely hydrated transport is higher than other structures, which contributes to the increase of overall performance. On the other hand, DFT results show the low basicity and strong hydrophily of cation containing multi-PEG substituents leads to the poor performance of PBP-TPEG. Therefore, for the design of AEMs mol. structures with outstanding performances, hydrophilic PEG spacer chain is more effective than hydrophobic alkyl spacer chain, and PEG is more effective as a spacer chain than as an extender chain. The experimental part of the paper was very detailed, including the reaction process of 1-Methyl-4-piperidone(cas: 1445-73-4Electric Literature of C6H11NO)

1-Methyl-4-piperidone(cas: 1445-73-4) is a member of piperidine. Piperidine is ubiquitous structural motif widely occurred in diverse synthetically and naturally occurring bioactive molecules. Piperidines are an immensely important class of compounds medicinally: the piperidine ring is the most common heterocyclic subunit among FDA approved drugs.Electric Literature of C6H11NO

Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem