1
|
Sibilska-Kaminski IK, Sicinski RR, Plum LA, DeLuca HF. Synthesis and Biological Activity of 2,22-Dimethylene Analogues of 19-Norcalcitriol and Related Compounds. J Med Chem 2020; 63:7355-7368. [PMID: 32510210 DOI: 10.1021/acs.jmedchem.0c00580] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Continuing our search for vitamin D analogues, we explored the modification of the steroidal side chain and inserted a methylene moiety in position C-22 together with either lengthening the side chain or introducing a ring at the terminal end. Our conformational studies confirmed that the presence of a methylene group attached to C-22 restricts the conformational flexibility of the side chain, which can result in changes in biological characteristics of a molecule. All synthesized 1α,25-dihydroxy-2,22-dimethylene-19-norvitamin D3 analogues proved equal to calcitriol in their ability to bind to the vitamin D receptor, and most of them exert significantly higher differentiation and transcriptional activity than calcitriol. The most active compounds were characterized by the presence of an elongated side chain or 26,27-dimethylene bridge. The synthetic strategy was based on the Wittig-Horner coupling of the known A-ring phosphine oxide with the corresponding Grundmann ketones prepared from a 20-epi-Inhoffen-Lythgoe diol derived from vitamin D2.
Collapse
Affiliation(s)
- Izabela K Sibilska-Kaminski
- Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Drive, Madison, Wisconsin 53706, United States
| | - Rafal R Sicinski
- Department of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland
| | - Lori A Plum
- Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Drive, Madison, Wisconsin 53706, United States
| | - Hector F DeLuca
- Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Drive, Madison, Wisconsin 53706, United States
| |
Collapse
|
2
|
Flores A, Sicinski RR, Grzywacz P, Thoden JB, Plum LA, Clagett-Dame M, DeLuca HF. A 20S combined with a 22R configuration markedly increases both in vivo and in vitro biological activity of 1α,25-dihydroxy-22-methyl-2-methylene-19-norvitamin D3. J Med Chem 2012; 55:4352-66. [PMID: 22490010 DOI: 10.1021/jm300187x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Six new analogues of 1α,25-dihydroxy-19-norvitamin D(3) (3a-4b, 5, and 6) were prepared by a convergent synthesis applying the Wittig-Horner reaction as a key step. The influence of methyl groups at C-22 on their biological activity was examined. It was established that both in vitro and in vivo activity is strongly dependent on the configuration of the stereogenic centers at C-20 and C-22. Introduction of the second methyl group at C-22 (analogues 5 and 6) generates the compounds that are slightly more potent than 1α,25-(OH)(2)D(3) in the in vitro tests but much less potent in vivo. The greatest in vitro and in vivo biological activity was achieved when the C-20 is in the S configuration and the C-22 is in the R configuration. The building blocks for the synthesis, the respective (20R,22R)-, (20R,22S)-, (20S,22R)-, and (20S,22S)-diols, were obtained by fractional crystallization of mixtures of the corresponding diastereomers. Structures and absolute configurations of the diols 21a, 21b, and 22a as well as analogues 3a, 5, and 6 were confirmed by the X-ray crystallography.
Collapse
Affiliation(s)
- Agnieszka Flores
- Department of Biochemistry, College of Agriculture and Life Sciences, University of Wisconsin-Madison , 433 Babcock Drive, Madison, Wisconsin 53706-1544, United States
| | | | | | | | | | | | | |
Collapse
|
3
|
Yamamoto K, Inaba Y, Yoshimoto N, Choi M, DeLuca HF, Yamada S. 22-Alkyl-20-epi-1α,25-dihydroxyvitamin D3 Compounds of Superagonistic Activity: Syntheses, Biological Activities and Interaction with the Receptor. J Med Chem 2007; 50:932-9. [PMID: 17298045 DOI: 10.1021/jm060889f] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We previously reported that 22R-methyl-20-epi-1,25-(OH)2D3 (3) possesses strong binding affinity for the vitamin D receptor (VDR) and shows superagonistic biological activities. To examine the effect of the length of an alkyl substituent at C(22) and to extend our compound library, we successfully synthesized 22R-ethyl-20-epi-1,25-(OH)2D3 (4) and 22R-butyl-20-epi-1,25-(OH)2D3 (5). Surprisingly, 22-ethyl analogue 4 showed stronger VDR binding affinity and transactivation potency than the superagonist of methyl analogue 3, but its calcemic activity in vivo was weaker than that of both the methyl analogue 3 and the natural hormone (1), while 22-butyl analogue 5 showed activities comparable to those of the hormone (1). A study of the docking of these new analogues to the VDR-LBD and alanine scanning mutational analysis demonstrated that 22-methyl and 22-ethyl substituents enhance the favorable hydrophobic interactions with residues lining the ligand binding pocket of the VDR, and that 22-butyl analogue 5 binds to the VDR by an induced fit mechanism.
Collapse
Affiliation(s)
- Keiko Yamamoto
- Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10 Kanda-Surugadai, Tokyo 101-0062, Japan.
| | | | | | | | | | | |
Collapse
|
4
|
Shimizu M, Yamamoto K, Mihori M, Iwasaki Y, Morizono D, Yamada S. Two-dimensional alanine scanning mutational analysis of the interaction between the vitamin D receptor and its ligands: studies of A-ring modified 19-norvitamin D analogs. J Steroid Biochem Mol Biol 2004; 89-90:75-81. [PMID: 15225750 DOI: 10.1016/j.jsbmb.2004.03.088] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
To clarify the structure-function relationship (SFR) of vitamin D analogs in terms of their interaction with the vitamin D receptor (VDR), we have proposed a new approach, two-dimensional alanine scanning mutational analysis (2D-ASMA). In this paper, attention was focused on the interactions around the A-ring of vitamin D. For this purpose, we synthesized four new 2-substituted 19-norvitamin D derivatives (3-6). The VDR affinity (3-6: 1, 5, 2 and 1/140, respectively) and transcriptional activity (3-6: 10, 30, 2 and 0.3, respectively) of the four compounds were evaluated relative to 1,25-(OH)(2)D(3) (5) (normalized to 1). Then, the transcriptional activities of wild-type and 18 mutant VDRs induced by the four compounds (3-6) were investigated. The results of this 18 x 4 2D-ASMA were presented as a patch table, and the effects of the mutations were analyzed in comparison with the natural hormone (1) and 2-methylene-19-nor-20-epi-1,25-(OH)(2)D(3) (2MD, 2). Of the four A-ring analogs, the 2alpha-hydroxyethoxy derivative (3) showed striking differences in the pattern on the patch table. From the results, we suggest a docking mode of this compound (3) in which the A-ring adopts the alpha conformation.
Collapse
Affiliation(s)
- Masato Shimizu
- School of Biomedical Science, Tokyo Medical and Dental University, Tokyo 101-0062, Japan
| | | | | | | | | | | |
Collapse
|
5
|
Choi M, Yamamoto K, Itoh T, Makishima M, Mangelsdorf DJ, Moras D, DeLuca HF, Yamada S. Interaction between vitamin D receptor and vitamin D ligands: two-dimensional alanine scanning mutational analysis. CHEMISTRY & BIOLOGY 2003; 10:261-70. [PMID: 12670540 DOI: 10.1016/s1074-5521(03)00050-4] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We present a new method to investigate the details of interaction between vitamin D nuclear receptor (VDR) and various ligands, namely a two-dimensional alanine scanning mutational analysis. In this method, the transactivation of various ligands is studied in conjunction with a series of alanine scanning mutations of the residues lining the ligand binding pocket (LBP) of VDR, and the complete set of results is profiled in a patch table. We investigated examples from four structurally diverse groups of known VDR ligands: the native vitamin D hormone and two compounds with the same side chain configuration; four 20-epi compounds; three 19-nor compounds; and two nonsecosteroids. The patch table of the results indicates characteristics of each group in terms of its interaction with 18 LBP residues. We demonstrate the validity of this approach by application to docking studies of the two nonsecosteroids.
Collapse
Affiliation(s)
- Mihwa Choi
- Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10, Kanda-Surugadai, Chiyoda-ku, 101-0062, Tokyo, Japan
| | | | | | | | | | | | | | | |
Collapse
|
6
|
Yamada S, Shimizu M, Yamamoto K. Structure-function relationships of vitamin D including ligand recognition by the vitamin D receptor. Med Res Rev 2003; 23:89-115. [PMID: 12424754 DOI: 10.1002/med.10023] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
First, the general structure and function of nuclear receptors (NRs) are described briefly to help our understanding of the mechanism of action of vitamin D mediated by the vitamin D receptor (VDR), a member of the NRs. Then we discuss the structure-function relationship (SFR) of vitamin D on the basis of ligand structures and the interaction of the ligand with the VDR. The SFR of vitamin D side chain analogs is discussed extensively in terms of our active space group concept, which was derived from conformational analyses of the side chains of vitamin D analogs and from studies with conformationally restricted 22-methyl-1,25-(OH)(2)D(3) isomers. The mobile area of the side chain of vitamin D can be grouped into five regions (E, G, EA, EG, and F), and the SFR has been analyzed in terms of these spatial regions. The SFR of ligand/VDR interaction is discussed on the basis of the crystal structure of VDR-LBD(delta 165-215), docking of various vitamin D ligands into the ligand binding pocket (LBP) of the VDR, and functional analysis of amino acids lining the LBP. Finally, we discuss total SFR, combining the results of the two approaches, and future aspects of structure-based design of vitamin D analogs.
Collapse
Affiliation(s)
- Sachiko Yamada
- Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-0062, Japan.
| | | | | |
Collapse
|
7
|
Choi M, Yamamoto K, Masuno H, Nakashima K, Taga T, Yamada S. Ligand recognition by the vitamin D receptor. Bioorg Med Chem 2001; 9:1721-30. [PMID: 11425573 DOI: 10.1016/s0968-0896(01)00060-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Three-dimensional structure of the ligand binding domain (LBD) of the vitamin D receptor (VDR) docked with the natural ligand 1 alpha,25-dihydroxyvitamin D(3) [1,25-(OH)(2)D(3)] has been mostly solved by the X-ray crystallographic analysis of the deletion mutant (VDR-LBD Delta 165-215). The important focus, from now on, is how the VDR recognizes and interacts with potent synthetic ligands. We now report the docking models of the VDR with three functionally and structurally interesting ligands, 22-oxa-1,25-(OH)(2)D(3) (OCT), 20-epi-1,25-(OH)(2)D(3) and 20-epi-22-oxa-24,26,27-trihomo-1,25-(OH)(2)D(3). In parallel with the computational docking studies, we prepared twelve one-point mutants of amino acid residues lining the ligand binding pocket of the VDR and examined their transactivation potency induced by 1,25-(OH)(2)D(3) and these synthetic ligands. The results indicate that L233, R274, W286, H397 and Y401 are essential for holding the all ligands tested, S278 and Q400 are not important at all, and the importance of S237, V234, S275, C288 and H305 is variable depending on the side-chain structure of the ligands. Based on these studies, we suggested key structural factors to bestow the selective action on OCT and the augmented activities on 20-epi-ligands. Furthermore, the docking models coincided well with our proposed active space-region theory of vitamin D based on the conformational analyses of ligands.
Collapse
Affiliation(s)
- M Choi
- Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10, Surugadai Kanda, Chiyoda-ku, Tokyo 101-0062, Japan
| | | | | | | | | | | |
Collapse
|
8
|
Yamada S, Yamamoto K, Masuno H, Choi M. Three-dimensional structure-function relationship of vitamin D and vitamin D receptor model. Steroids 2001; 66:177-87. [PMID: 11179725 DOI: 10.1016/s0039-128x(00)00145-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
On the basis of conformational analysis of the vitamin D side chain and studies using conformationally restricted synthetic vitamin D analogs, we have suggested the active space region concept of vitamin D: The vitamin D side-chain region was grouped into four regions (A, G, EA and EG) and the A and EA regions were suggested to be important for vitamin D actions. We extended our theory to known highly potent vitamin D analogs and found a new region F. The analogs which occupy the F region have such modifications as 22-oxa, 22-ene, 16-ene and 18-nor. Altogether, the following relationship between the space region and activity was found: Affinity for vitamin D receptor (VDR), EA > A> F > G > EG; Affinity for vitamin D binding protein (DBP), A >> G,EA,EG; Target gene transactivation, EA > F > A > EG > or = G; Cell differentiation, EA > F > A > EG > or = G; Bone calcium mobilization, EA > GA > F > or = EG; Intestinal calcium absorption, EA = A > or = G >> EG. We modeled the 3D structure of VDR-LBD (ligand binding domain) using hRARgamma as a template, to develop our structure-function theory into a theory involving VDR. 1alpha,25(OH)(2)D(3) was docked into the ligand binding pocket of the VDR with the side chain heading the wide cavity at the H-11 site, the A-ring toward the narrow beta-turn site, and the beta-face of the CD ring facing H3. Amino acid residues forming hydrogen bonds with the 1alpha- and 25-OH groups were specified: S237 and R274 forming a pincer type hydrogen-bond for the 1alpha-OH and H397 for the 25-OH. Mutants of several amino acid residues that are hydrogen-bond candidates were prepared and their biologic properties were evaluated. All of our mutation results together with known mutation data support our VDR model docked with the natural ligand.
Collapse
Affiliation(s)
- S Yamada
- Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10 Kanda-Surugadai, Chiyoda-ku, 101-0062, Tokyo, Japan. yamada@i-mde,tmd.ac.jp
| | | | | | | |
Collapse
|
9
|
Konno K, Fujishima T, Maki S, Liu Z, Miura D, Chokki M, Ishizuka S, Yamaguchi K, Kan Y, Kurihara M, Miyata N, Smith C, DeLuca HF, Takayama H. Synthesis, biological evaluation, and conformational analysis of A-ring diastereomers of 2-methyl-1,25-dihydroxyvitamin D(3) and their 20-epimers: unique activity profiles depending on the stereochemistry of the A-ring and at C-20. J Med Chem 2000; 43:4247-65. [PMID: 11063621 DOI: 10.1021/jm000261j] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
All eight possible A-ring diastereomers of 2-methyl-1, 25-dihydroxyvitamin D(3) (2) and 2-methyl-20-epi-1, 25-dihydroxyvitamin D(3) (3) were convergently synthesized. The A-ring enyne synthons 19 were synthesized starting with methyl (S)-(+)- or (R)-(-)-3-hydroxy-2-methylpropionate (8). This was converted to the alcohol 14 as a 1:1 epimeric mixture in several steps. After having been separated by column chromatography, each isomer led to the requisite A-ring enyne synthons 19 again as 1:1 mixtures at C-1. Coupling of the resulting A-ring enynes 20a-h with the CD-ring portions 5a,b in the presence of a Pd catalyst afforded the 2-methyl analogues 2a-h and 3a-h in good yield. In this way, all possible A-ring diastereomers were synthesized. The synthesized analogues were biologically evaluated both in vitro and in vivo. The potency was highly dependent on the stereochemistry of each isomer. In particular, the alpha alpha beta-isomer 2g exhibited 4-fold higher potency than 1 alpha,25-dihydroxyvitamin D(3) (1) both in bovine thymus VDR binding and in elevation of rat serum calcium concentration and was twice as potent as the parent compound in HL-60 cell differentiation. Furthermore, its 20-epimer, that is, 20-epi-alpha alpha beta 3g, exhibited exceptionally high activities: 12-fold higher in VDR binding affinity, 7-fold higher in calcium mobilization, and 590-fold higher in HL-60 cell differentiation, as compared to 1 alpha,25-dihydroxyvitamin D(3) (1). Accordingly, the double modification of 2-methyl substitution and 20-epimerization resulted in unique activity profiles. Conformational analysis of the A-ring by (1)H NMR and an X-ray crystallographic analysis of the alpha alpha beta-isomer 2g are also described.
Collapse
Affiliation(s)
- K Konno
- Faculty of Pharmaceutical Sciences, Teikyo University, Sagamiko, Kanagawa 199-0195, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Yamamoto K, Masuno H, Choi M, Nakashima K, Taga T, Ooizumi H, Umesono K, Sicinska W, VanHooke J, DeLuca HF, Yamada S. Three-dimensional modeling of and ligand docking to vitamin D receptor ligand binding domain. Proc Natl Acad Sci U S A 2000; 97:1467-72. [PMID: 10677485 PMCID: PMC26457 DOI: 10.1073/pnas.020522697] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The ligand binding domain of the human vitamin D receptor (VDR) was modeled based on the crystal structure of the retinoic acid receptor. The ligand binding pocket of our VDR model is spacious at the helix 11 site and confined at the beta-turn site. The ligand 1alpha, 25-dihydroxyvitamin D(3) was assumed to be anchored in the ligand binding pocket with its side chain heading to helix 11 (site 2) and the A-ring toward the beta-turn (site 1). Three residues forming hydrogen bonds with the functionally important 1alpha- and 25-hydroxyl groups of 1alpha,25-dihydroxyvitamin D(3) were identified and confirmed by mutational analysis: the 1alpha-hydroxyl group is forming pincer-type hydrogen bonds with S237 and R274 and the 25-hydroxyl group is interacting with H397. Docking potential for various ligands to the VDR model was examined, and the results are in good agreement with our previous three-dimensional structure-function theory.
Collapse
Affiliation(s)
- K Yamamoto
- Institute of Biomaterial, Medical Research Institute, Tokyo Medical and Dental University, 2-3-10, Surugadai Kanda, Chiyoda-ku, Tokyo 101-0062 Japan
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Yamamoto K, Ooizumi H, Umesono K, Verstuyf A, Bouillon R, DeLuca HF, Shinki T, Suda T, Yamada S. Three-dimensional structure-function relationship of vitamin D: side chain location and various activities. Bioorg Med Chem Lett 1999; 9:1041-6. [PMID: 10230636 DOI: 10.1016/s0960-894x(99)00129-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The various biological activities of side-chain mobility restricted analogs, four diastereomers at C(20) and C(22) of 22-methyl-1alpha,25-dihydroxyvitamin D3, were evaluated. The relationship between structure and the various activities of the analogs was discussed in terms of the active space region concept that we previously suggested.
Collapse
Affiliation(s)
- K Yamamoto
- Institute for Medical and Dental Engineering, Tokyo Medical and Dental University, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Yamamoto K, Ogura H, Jukuta JI, Inoue H, Hamada K, Sugiyama Y, Yamada S. Stereochemical and Mechanistic Studies on Conjugate Addition of Organocuprates to Acyclic Enones and Enoates: Simple Rule for Diastereofacial Selectivity. J Org Chem 1998. [DOI: 10.1021/jo980308x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Keiko Yamamoto
- Institute for Medical and Dental Engineering, Tokyo Medical and Dental University, 2-3-10 Surugadai Kanda, Chiyoda-ku, Tokyo 101, Japan
| | - Hiroshi Ogura
- Institute for Medical and Dental Engineering, Tokyo Medical and Dental University, 2-3-10 Surugadai Kanda, Chiyoda-ku, Tokyo 101, Japan
| | - Jun-ichi Jukuta
- Institute for Medical and Dental Engineering, Tokyo Medical and Dental University, 2-3-10 Surugadai Kanda, Chiyoda-ku, Tokyo 101, Japan
| | - Hiroko Inoue
- Institute for Medical and Dental Engineering, Tokyo Medical and Dental University, 2-3-10 Surugadai Kanda, Chiyoda-ku, Tokyo 101, Japan
| | - Kazuhiro Hamada
- Institute for Medical and Dental Engineering, Tokyo Medical and Dental University, 2-3-10 Surugadai Kanda, Chiyoda-ku, Tokyo 101, Japan
| | - Youko Sugiyama
- Institute for Medical and Dental Engineering, Tokyo Medical and Dental University, 2-3-10 Surugadai Kanda, Chiyoda-ku, Tokyo 101, Japan
| | - Sachiko Yamada
- Institute for Medical and Dental Engineering, Tokyo Medical and Dental University, 2-3-10 Surugadai Kanda, Chiyoda-ku, Tokyo 101, Japan
| |
Collapse
|
13
|
Martínez-Pérez J, Sarandeses L, Granja J, Palenzuela J, Mouriño A. Design and synthesis of 1α,25-dihydroxyvitamin D3 analogues with fixed torsion angle C(16-17-20-22). Tetrahedron Lett 1998. [DOI: 10.1016/s0040-4039(98)00867-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
14
|
Yamada S, Yamamoto K, Masuno H, Ohta M. Conformation-function relationship of vitamin D: conformational analysis predicts potential side-chain structure. J Med Chem 1998; 41:1467-75. [PMID: 9554880 DOI: 10.1021/jm970761l] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
In previous studies, we have grouped regions in space occupied by the vitamin D side chain into four: A, G, EA, and EG. We showed that the receptor (VDR) affinity of 1alpha,25-dihydroxyvitamin D3 derivatives increases, in terms of side-chain region, in the order EG, G, A, and EA. We called this the active space group concept. In the present study, we used this active space group concept to analyze the conformation-activity relationship of about 40 representative potent 1alpha,25-dihydroxyvitamin D3 analogues. We initially listed structural modifications in the side chain of potent vitamin D analogues and estimated their potency factor. Possible side-chain conformations of representative analogues were calculated by the molecular mechanics method and plotted on a dot map compared with the regions A, G, EA, and EG. The cell-differentiating potency of the analogues was correlated with our active space group concept with few exceptions. Among potent analogues with a natural configuration at C(20), the side chains of those with a 22-oxa, 22-ene, 16-ene, or a 18-nor modification were located in front of region EA (termed F). The side chains of the most potent 20-epi-22-oxa-24-homovitamin D analogues were concentrated at the left side of the EA region (L-EA). Thus, the side chains of almost all potent analogues were distributed around the EA region, and potency increased in the order A, F, EA, and L-EA.
Collapse
Affiliation(s)
- S Yamada
- Institute for Medical and Dental Engineering, Tokyo Medical and Dental University, 2-3-10 Surugadai Kanda, Chiyoda-ku, Tokyo 101, Japan
| | | | | | | |
Collapse
|
15
|
Iwasaki Y, Shimizu M, Hirosawa T, Yamada S. Regioselective synthesis of 19-fluorovitamin D via fluorination of vitamin D-sulfur dioxide adducts. Tetrahedron Lett 1996. [DOI: 10.1016/s0040-4039(96)01459-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
16
|
Yamamoto K, Sun WY, Ohta M, Hamada K, DeLuca HF, Yamada S. Conformationally restricted analogs of 1 alpha, 25-dihydroxyvitamin D3 and its 20-epimer: compounds for study of the three-dimensional structure of vitamin D responsible for binding to the receptor. J Med Chem 1996; 39:2727-37. [PMID: 8709103 DOI: 10.1021/jm9600048] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Two proteins play important roles in the expression of vitamin D function: the specific nuclear receptor protein (vitamin D receptor, VDR) and the transport protein (vitamin D binding protein, DBP). This study was conducted to clarify the conformation of vitamin D responsible for binding to those proteins. For the purpose, the side chain mobility of 1,25(OH)2D3 (1) and its 20-epimer, 20-epi-1,25(OH)2D3 (2), was analyzed by a systematic conformational search. The results were depicted as a three-dimensional dot map, which indicates that the side chains of the two vitamins (1 and 2) occupy different spatial regions that are separated in two areas. We denoted these areas as A and G for 1 and EA and EG for 2. Four analogs, the diastereomers at C(20) and C(22) (3-6) of 22-methylated 1,25(OH)2D3 whose side chains were confined to occupy G, A, EA, and EG, respectively, were designed. These analogs (3-6) were synthesized efficiently by a stereoselective conjugate addition of organocuprate to steroidal E- and Z-22-en-24-ones as the key step. In binding to the VDR the affinities of the analogs (3-6) relative to 1,25-(OH)2D3 (1) were 1/60, 1/3, 20, and 1/100, respectively. These results indicate that the A region is responsible for binding of 1 to VDR and the EA region for binding of 2. Only isomer 4 showed significant affinity for DBP, indicating only the A region is responsible for binding to DBP. Thus, 5 showed clear separation of binding affinities for two proteins, VDR and DBP. Having the highest known VDR affinity, (22R)-22-methyl-20-epi-1,25(OH)2D3 (5) has potential both as a therapeutic agent and as a tool to study the molecular mechanism of vitamin D-mediated gene transcription.
Collapse
Affiliation(s)
- K Yamamoto
- Institute for Medical and Dental Engineering, Tokyo Medical and Dental University, Japan
| | | | | | | | | | | |
Collapse
|