A method for generating planar fused ring backbones suitable for energetic molecule design

Abstract

The application discloses a method for generating a planar fused ring skeleton suitable for energetic molecule design. The method realizes generation of the planar fused ring skeleton suitable for the energetic molecule design through steps of initial ring structure setting, fused ring structure type selection, bonding in the ring, nitrogen substitution / oxo fused ring, double bond fused ring and fused ring planarity evaluation, and overcomes the problem of low structural novelty caused by evolution based on an existing fused ring skeleton in a traditional method.

Description

Technical Field

[0001] This invention relates to a method for generating fused ring skeletons, and more particularly to a planar fused ring skeleton generation method suitable for the design of energetic molecules. Background Technology

[0002] Planar fused-ring energetic molecules, due to the conjugation of π electrons within the fused ring, can enhance molecular stability and are considered a class of safe energetic materials. Current energetic molecule design primarily employs a "skeleton structure + group structure" approach. Therefore, the planar fused-ring framework is the foundation for constructing planar fused-ring energetic molecules. To ensure excellent energy performance in the designed planar fused-ring energetic molecules, their framework structure generally requires nitrogen / oxygen elements and is of a binary, ternary, or quaternary structure.

[0003] Existing designs of planar fused-ring backbones are mostly based on reported planar fused-ring backbones and are carried out through nitrogen / oxygen atom substitution based on the chemical intuition of experimental scientists. This has problems such as generating a small number of backbones and difficulty in obtaining fused-ring backbones with varying ring numbers. As a result, the sample size of subsequent planar fused-ring energetic molecules is small and the structure is limited to the subjective understanding of the designers, thus affecting the performance of planar fused-ring energetic molecules. Summary of the Invention

[0004] To address existing defects or shortcomings, this invention provides a planar fused ring framework generation method suitable for the design of energetic molecules.

[0005] Therefore, the planar fused ring framework generation method for energetic molecule design provided by the present invention includes:

[0006] Step 1: Construct an initial ring structure, which consists of multiple carbon atoms connected by single bonds between adjacent carbon atoms, wherein the number of carbon atoms is m, and m≥4;

[0007] Step 2: Construct several fused ring frameworks based on the initial ring structure. The several fused ring frameworks include multiple binary fused ring frameworks, multiple ternary fused ring frameworks, and / or multiple quaternary fused ring frameworks. The binary fused ring framework is formed by connecting single bonds between any two non-adjacent atoms in the initial ring structure. The ternary fused ring framework is formed by connecting single bonds between any two non-adjacent atoms in the binary fused ring framework structure. The quaternary fused ring framework is formed by connecting single bonds between any two non-adjacent atoms in the ternary fused ring framework structure.

[0008] Step 3: Under the premise of ensuring structural stability, replace one or more carbon atoms in each fused ring framework with nitrogen atoms and / or oxygen atoms; to obtain several energetic fused ring frameworks.

[0009] Step 4: Under the premise of ensuring structural stability, replace one or more C-C single bonds in each energetic fused ring framework structure with C=C; to obtain several energetic fused ring frameworks containing double bonds.

[0010] Step 5: Select structures with low planarity from several energetic fused ring frameworks containing double bonds as target planar fused ring frameworks.

[0011] An alternative approach is to obtain the SMILES encoding of the initial ring structure using ChemDraw software in step 1.

[0012] An alternative approach is to implement the connection of a single bond between any two non-adjacent atoms in step 2 as follows: use Python programming to identify the total number of atoms in the ring structure and label the atomic numbers in the ring structure; select any two non-adjacent atoms; and use the AddBond() subroutine of the RDKit open-source software package to add a single bond between the two non-adjacent atoms.

[0013] An optional approach is that step 3 includes: using the RDKit open-source software package to identify the carbon atom position numbers in the CH and CH2 substructures of the fused ring backbone; then replacing one or more carbon atoms in the identified CH substructure with nitrogen atoms and / or replacing one or more carbon atoms in the identified CH2 substructure with oxygen atoms.

[0014] An optional approach is that step 4 includes: using the RDKit open-source software package to determine the number of single bonds (band-total) and the atomic indices (x) at both ends of the i-th single bond within each energetic fused ring backbone. i and y i band-total≥1, i<=band-total; use the GetNeighbors() and GetSymbol() subroutines to identify atom x. i and y i Check if there are hydrogen atoms in adjacent atoms; if both contain hydrogen atoms, use the SetBondType() subroutine to set the atom x. i and y i The chemical bonds between them change from single bonds to double bonds.

[0015] An optional approach is that step 5 includes obtaining the three-dimensional structures of each energetic fused ring framework containing double bonds, calculating the flatness of each three-dimensional structure using the CalcPBF() subroutine, and selecting structures with a flatness less than [a certain value]. An energetic fused ring framework containing double bonds is used as the target planar fused ring framework. A further alternative is to obtain the three-dimensional structure of the fused ring framework using AllChem.EmbedMolecule().

[0016] An alternative approach is that the method includes:

[0017] S1, Input the total number of atoms in the initial ring structure;

[0018] S2, obtain the SMILES code of the initial ring structure; S3, input the type of fused ring structure to be generated, wherein the type of fused ring structure to be generated is a binary fused ring skeleton, a ternary fused ring skeleton or / and a quaternary fused ring skeleton.

[0019] S4, Based on the fused ring structure type input in step S3, construct several fused ring skeletons using an intra-ring bridging method. The intra-ring bridging step includes:

[0020] S4-1, for binary fused ring framework, connects single bonds between any two non-adjacent atoms in the initial ring structure to form a binary fused ring structure;

[0021] S4-2, for a ternary fused ring framework, a single bond is connected between any two non-adjacent atoms in the initial ring structure to form a binary fused ring framework; a single bond is connected between any two non-adjacent atoms in any ring structure in the binary fused ring framework to form a ternary fused ring framework.

[0022] S4-3, for a four-membered fused ring framework, a single bond is connected between any two non-adjacent atoms in the initial ring structure to form a two-membered fused ring framework; a single bond is connected between any two non-adjacent atoms in any ring structure in the two-membered fused ring framework to form a three-membered fused ring framework; a single bond is connected between any two non-adjacent atoms in any ring structure in the three-membered fused ring framework to form a four-membered fused ring framework.

[0023] S5. Under the premise of ensuring structural stability, one or more carbon atoms in each fused ring framework are replaced with nitrogen atoms and / or oxygen atoms to obtain several energetic fused ring frameworks.

[0024] S6. Under the premise of ensuring structural stability, replace one or more CC single bonds in each energetic fused ring framework structure with C=C; to obtain several energetic fused ring frameworks containing double bonds.

[0025] S7. Obtain the three-dimensional structures of each energetic fused-ring framework containing double bonds, and calculate the flatness of each three-dimensional structure using the CalcPBF() subroutine; select structures with a flatness less than... An energetic fused ring framework containing double bonds is used as the target planar fused ring framework.

[0026] This invention solves the problems of generating a small number of fused ring skeletons and difficulty in obtaining fused ring skeletons with varying ring numbers in current planar fused ring skeleton designs applicable to energetic molecules, and realizes the design of binary, ternary or quaternary planar fused ring structures applicable to energetic molecule designs.

[0027] The method of this invention can construct a planar fused ring framework structure suitable for the design of energetic molecules by performing multiple intra-ring bridging, nitrogen / oxygen substitution, double bond formation, and other operations based on the target planar fused ring framework structure requirements such as the total number of atoms and the number of rings. The final planar fused ring framework structure is obtained by using planarity calculation methods and screening criteria. This method has a simple and fast design concept and helps to improve the design and development efficiency of planar fused ring energetic molecules. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the method flow in an embodiment of the present invention.

[0029] Figure 2 Examples of binary, ternary, and quaternary fused ring framework structures with a total number of 16 atoms in the framework of this invention;

[0030] Figure 3 The results of nitrogen / oxygenation, double bondation, and flatness evaluation of the binary fused ring 2f-0 in the embodiments of the present invention are shown. Detailed Implementation

[0031] Unless otherwise specified, the scientific and technical terms used in this article are intended for understanding by those skilled in the art.

[0032] The method of this invention can be implemented using existing open-source software. To make the objectives, technical solutions, and advantages of this invention clearer, the invention is further described below with reference to embodiments. These embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, other embodiments obtained by those skilled in the art without creative effort are all within the protection scope of this invention.

[0033] Example:

[0034] This embodiment is based on the solution of the present invention, and also employs, as follows: Figure 1 The flowchart shown is for generating planar fused ring frameworks suitable for energetic molecule design. First, input the total number of atoms in the framework (16), and obtain the SMILES code of the initial ring structure using ChemDraw software; then execute S3-7:

[0035] S3, Input the type of fused ring structure to be generated. In this embodiment, the types of fused ring structures to be generated are binary fused ring skeletons, ternary fused ring skeletons and quaternary fused ring skeletons.

[0036] S4, Based on the fused ring structure type input in step S3, construct several fused ring skeletons using an intra-ring bridging method. The intra-ring bridging step includes:

[0037] S4-1, for binary fused ring framework, connects single bonds between any two non-adjacent atoms in the initial ring structure to form a binary fused ring structure;

[0038] S4-2, for a ternary fused ring framework, a single bond is connected between any two non-adjacent atoms in the initial ring structure to form a binary fused ring framework; a single bond is connected between any two non-adjacent atoms in any ring structure in the binary fused ring framework to form a ternary fused ring framework.

[0039] S4-3, for a four-membered fused ring framework, a single bond is connected between any two non-adjacent atoms in the initial ring structure to form a two-membered fused ring framework; a single bond is connected between any two non-adjacent atoms in any ring structure in the two-membered fused ring framework to form a three-membered fused ring framework; a single bond is connected between any two non-adjacent atoms in any ring structure in the three-membered fused ring framework to form a four-membered fused ring framework.

[0040] The method for connecting any two non-adjacent atoms with a single bond is as follows: use Python programming to identify the total number of atoms in the ring structure and label the atomic number of each atom in the ring structure; select any two non-adjacent atoms; use the AddBond() subroutine of the RDKit open-source software package to add a single bond between the two non-adjacent atoms.

[0041] S5. Under the premise of ensuring structural stability, one or more carbon atoms in each fused ring framework are replaced with nitrogen atoms and / or oxygen atoms to obtain several energetic fused ring frameworks. Specifically, the RDKit open-source software package is used to identify the carbon atom position numbers in the CH substructure and CH2 substructure of the fused ring framework. Then, one or more carbon atoms in the identified CH substructure are replaced with nitrogen atoms and / or one or more carbon atoms in the identified CH2 substructure are replaced with oxygen atoms.

[0042] S6. Under the premise of ensuring structural stability, replace one or more C=C single bonds in each energetic fused ring framework structure with C=C; obtain several energetic fused ring frameworks containing double bonds; specifically, use the RDKit open source software package to determine the number of single bonds band-total and the atomic indices x at both ends of the i-th single bond in each energetic fused ring framework. i and y i band-total≥1, i<=band-total; use the GetNeighbors() and GetSymbol() subroutines to identify atom x. i and y i Check if there are hydrogen atoms in adjacent atoms; if both contain hydrogen atoms, use the SetBondType() subroutine to set the atom x. i and y iThe chemical bonds between them change from single bonds to double bonds; GetNeighbors(): retrieves the atomic structure of the positions near the atom being studied (outputs the atomic structure); GetSymbol(): retrieves the symbolic representation of the atomic structure (outputs the symbolic representation of atom types such as H, C, O, etc.);

[0043] S7. The three-dimensional structures containing energetic fused-ring frameworks with double bonds were obtained using AllChem.EmbedMolecule(), and the flatness of each structure was calculated using the CalcPBF() subroutine. Structures with a flatness less than [value missing] were selected. An energetic fused ring framework containing double bonds is used as the target planar fused ring framework.

[0044] This embodiment uses a ring structure with a total of 16 atoms as an example, such as... Figure 2 The fused ring structures are constructed as shown. In step Sample-S4-0, each carbon atom in the ring structure is first labeled from 1 to 16. For binary fused ring structures, a single-bridge method within the ring is used to construct 53 candidate structures; for ternary fused ring structures, a double-bridge method within the ring is used to construct 373 candidate structures; and for quaternary fused ring structures, a triple-bridge method within the ring is used to construct 531 candidate structures.

[0045] by Figure 2 Taking the 2f-0 structure as an example, the steps of nitrification / oxygenation, double bond formation, and planarity evaluation are illustrated. First, the carbon atom positions and the number of substructures in the "CH" and "CH2" substructures of the 2f-0 structure are determined. The carbon atoms in the "CH" substructure are 6 and 15, respectively, and the carbon atoms in the "CH2" substructure are 1-5 and 7-14, respectively. Then, for the "CH" substructure, three nitrified fused rings, 2f-0-N0 and 2f-0-N1, are obtained by using nitrogen atom substitution. Based on this, for the "CH2" substructure, 16382 candidate nitrified / oxygenated fused ring structures, such as 2f-0-N0-O0 and 2f-0-N0-O1, are obtained by using oxygen atom substitution.

[0046] See Figure 3The Sample-S6-1 step in the process involves constructing a double bond conversion operation based on the 2f-0-N0-O0 fused ring structure. First, the single bonds in the structure are identified, resulting in 18 single bonds: 5-6, 6-7, 7-12, 12-13, 13-14, 14-15, 15-6, 6-5, 5-4, 4-3, 3-2, 2-1, 1-8, 8-11, 11-10, 10-9, 9-16, and 16-15. Then, the adjacent atoms at both ends of these single bonds are identified, and it is determined whether hydrogen atoms are present in both. It is found that only the two bonds, 5-6, 6-7, and 6-15, do not meet the condition that adjacent atoms must contain hydrogen atoms. Therefore, bonds that meet the condition are selected, and any number of single bonds are replaced with double bonds, resulting in a total of 16201 candidate structures, such as 2f-0-N0-O0-d1 and 2f-0-N0-O0-d2.

[0047] Based on this, the three-dimensional structure of the fused ring skeleton was obtained using AllChem.EmbedMolecule() from the RDKit open-source software package. The flatness of the structure was calculated using the CalcPBF() subroutine based on the three-dimensional structure. Flatness was determined using the 2f-0-N0-O0-d1, 2f-0-N0-O0-d2, and quaternary fused ring 4f-N8-O1-d1 structures as examples. The results showed that the flatness of the three structures were as follows: and Only 4f-N8-O1-d1 satisfies the condition less than Requirements. See also. Figure 3 As can be seen from the front and side views of 4f-N8-O1-d1, the framework is indeed a planar structure, and contains 8 nitrogen atoms and 1 oxygen atom, making it a potential planar fused ring energetic framework.

[0048] It should also be noted that the above embodiments are only used to illustrate the present invention and are not intended to limit the present invention. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions also fall within the scope of the present invention, and the patent protection scope of the present invention should be defined by the claims.

Claims

1. A method for generating a planar fused-ring framework suitable for the design of energetic molecules, characterized in that, The methods include: Step 1: Construct an initial ring structure, which consists of multiple carbon atoms connected by single bonds between adjacent carbon atoms, wherein the number of carbon atoms is m, and m≥4; Step 2: Construct several fused ring frameworks based on the initial ring structure. The several fused ring frameworks include multiple binary fused ring frameworks, multiple ternary fused ring frameworks, and / or multiple quaternary fused ring frameworks. The binary fused ring framework is formed by connecting single bonds between any two non-adjacent atoms in the initial ring structure. The ternary fused ring framework is formed by connecting single bonds between any two non-adjacent atoms in the binary fused ring framework structure. The quaternary fused ring framework is formed by connecting single bonds between any two non-adjacent atoms in the ternary fused ring framework structure. Step 3: Under the premise of ensuring structural stability, replace one or more carbon atoms in each fused ring framework with nitrogen atoms and / or oxygen atoms; to obtain several energetic fused ring frameworks. Step 4: Under the premise of ensuring structural stability, replace one or more C-C single bonds in each energetic fused ring framework structure with C=C; to obtain several energetic fused ring frameworks containing double bonds. Step 5: Select structures with low planarity from several energetic fused ring frameworks containing double bonds as target planar fused ring frameworks.

2. The method for generating a planar fused-ring framework suitable for the design of energetic molecules according to claim 1, characterized in that, In step 1, the SMILES code of the initial ring structure is obtained using ChemDraw software.

3. The method for generating a planar fused-ring framework suitable for the design of energetic molecules according to claim 1, characterized in that, The method for connecting any two non-adjacent atoms with a single bond in step 2 is as follows: use Python programming to identify the total number of atoms in the ring structure and label the atomic number of each atom in the ring structure; select any two non-adjacent atoms; and use the AddBond() subroutine of the RDKit open-source software package to add a single bond between the two non-adjacent atoms.

4. The method for generating a planar fused-ring framework suitable for the design of energetic molecules according to claim 1, characterized in that, Step 3 includes: using the RDKit open-source software package to identify the carbon atom position numbers in the CH and CH2 substructures of the fused ring backbone; then replacing one or more carbon atoms in the identified CH substructure with nitrogen atoms and / or replacing one or more carbon atoms in the identified CH2 substructure with oxygen atoms.

5. The method for generating a planar fused-ring framework suitable for the design of energetic molecules according to claim 1, characterized in that, Step 4 includes: using the RDKit open-source software package to determine the number of single bonds (band-total) and the atomic indices x at both ends of the i-th single bond in each energetic fused ring backbone. i and y i band-total≥1, i<=band-total; use the GetNeighbors() and GetSymbol() subroutines to identify atom x. i and y i Check if there are hydrogen atoms in adjacent atoms; if both contain hydrogen atoms, use the SetBondType() subroutine to set the atom x. i and y i The chemical bonds between them change from single bonds to double bonds.

6. The method for generating a planar fused ring framework suitable for the design of energetic molecules according to claim 1, characterized in that, Step 5 includes obtaining the three-dimensional structures of each energetic fused-ring framework containing double bonds, calculating the flatness of each three-dimensional structure using the CalcPBF() subroutine, and selecting structures with a flatness less than [value missing]. An energetic fused ring framework containing double bonds is used as the target planar fused ring framework.

7. The method for generating a planar fused-ring framework suitable for the design of energetic molecules according to claim 6, characterized in that, The three-dimensional structure of the fused ring skeleton was obtained using AllChem.EmbedMolecule().

8. The method for generating a planar fused ring framework suitable for the design of energetic molecules according to claim 1, characterized in that, The method includes: S1, Input the total number of atoms in the initial ring structure; S2, obtain the SMILES code of the initial ring structure; S3, input the type of fused ring structure to be generated, wherein the type of fused ring structure to be generated is a binary fused ring skeleton, a ternary fused ring skeleton or / and a quaternary fused ring skeleton. S4, Based on the fused ring structure type input in step S3, construct several fused ring skeletons using an intra-ring bridging method. The intra-ring bridging step includes: S4-1, for binary fused ring framework, connects single bonds between any two non-adjacent atoms in the initial ring structure to form a binary fused ring structure; S4-2, for a ternary fused ring framework, a single bond is connected between any two non-adjacent atoms in the initial ring structure to form a binary fused ring framework; a single bond is connected between any two non-adjacent atoms in any ring structure in the binary fused ring framework to form a ternary fused ring framework. S4-3, for a four-membered fused ring framework, a single bond is connected between any two non-adjacent atoms in the initial ring structure to form a two-membered fused ring framework; a single bond is connected between any two non-adjacent atoms in any ring structure in the two-membered fused ring framework to form a three-membered fused ring framework; a single bond is connected between any two non-adjacent atoms in any ring structure in the three-membered fused ring framework to form a four-membered fused ring framework. S5. Under the premise of ensuring structural stability, one or more carbon atoms in each fused ring framework are replaced with nitrogen atoms and / or oxygen atoms to obtain several energetic fused ring frameworks. S6. Under the premise of ensuring structural stability, replace one or more CC single bonds in each energetic fused ring framework structure with C=C; to obtain several energetic fused ring frameworks containing double bonds. S7. Obtain the three-dimensional structures of each energetic fused-ring framework containing double bonds, and calculate the flatness of each three-dimensional structure using the CalcPBF() subroutine; select structures with a flatness less than... An energetic fused ring framework containing double bonds is used as the target planar fused ring framework.

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