pubchem-requests-python 0.0.4

A wrapper for the pubchem PUG REST API that simplifies retrieval of chemical information.

Pub Chem Requests

This package wraps the PubChem PUG REST and PUG View APIs, simplifying the retrieval of basic information about chemical compounds, including:

• Name
• Synonyms
• CAS Number
• CID Number (This is specific to PubChem)
• molecular formula
• molecular weight
• molar mass
• A list of descriptions
• A list of hazard statements (safety information)

Installation

pip install pubchem-requests-python

The Compound Class

A class containing information about a given chemical compound.

Fetching a compound

Compounds can be initialized from a name, CAS Number, or directly from a CID:

from pubchem_requests_python import (
    compound_from_name,
    compound_from_CAS,
    compound_from_CID,
)

# 3 ways to retrieve information about water
from_name = compound_from_name('water')
from_CAS = compound_from_CAS('7732-18-5')
from_CID = compound_from_CID('962')

If a compound is not found, the compound_from_X function will return None.

Notes:

• compound_from_CID is the most reliable, closely followed by compound_from_CAS. compound_from_name does not search synonyms and uses the name directly in the api call, meaning typos and spacing can directly affect the success of the function.

Getters

Each compound property has an associated getter function:

    def get_synonyms(self) -> list[str] | None
    def get_name(self) -> str | None
    def get_cas(self) -> str | None
    def get_descriptions(self) -> list[str] | None
    def get_molecular_formula(self) -> str | None
    def get_molecular_weight(self) -> float | None
    def get_molar_mass(self) -> float | None
    def get_safety_data(self) -> list[str] | None

Alternatively, the .dict() function will return a dictionary representing the compound with keys:

• "name": str | None
• "cas": str | None
• "cid": str | None
• "synonyms": list[str] | None
• "descriptions": list[str] | None
• "molecular_formula": str | None
• "molecular_weight": float | None
• "molar_mass": float | None
• "safety_data": list[str] | None

Note: It is possible for a compound to be found, but for some of its information to be missing/empty. In this case, the get fucntion for that property will return None, and the key for that property will map to None.

Future work

• The PUG View response contains 'Experimental Properties' which vary from compound to compound, but generally contain information about the physical form/appearance of a compound at room temperature, information about boiling point, odor, taste, etc. This could be incorporated into the compound class.
• Lower level logging.

Individual Requests

For convenience, the package also provides a set of functions to retrieve individual chemical properties:

def cas_to_cid(cas_number: str) -> str | None
def name_to_cid(compound_name: str) -> str | None
def cid_to_cas(cid: str) -> str | None
def cid_to_name(cid: str) -> str | None
def cid_to_names(cid: str) -> list[str] | None
def name_to_cas(compound_name: str) -> str | None
def cas_to_name(cas_number: str) -> str | None
def cas_to_names(cas_number: str) -> list[str] | None
def cid_to_molecular_weight(cid: str) -> float | None
def name_to_molecular_weight(compound_name: str) -> float | None
def cas_to_molecular_weight(cas_number: str) -> float | None
def cid_to_safety_data(cid: str) -> list[str] | None
def name_to_safety_data(name: str) -> list[str] | None
def cas_to_safety_data(cas_number: str) -> list[str] | None
def cid_to_molecular_formula(cid: str) -> str | None
def name_to_molecular_formula(name: str) -> str | None
def cas_to_molecular_formula(cas_number: str) -> str | None

Note: Initializing a compound takes ~the same amount of time as any one of these functions, and is therefore generally more efficient.