Bicyclic compounds and their use as antibacterial agents and β-lactamase inhibitors

1. A compound of formula (I):

wherein:

M is hydrogen or a pharmaceutically acceptable salt-forming cation;

Y is OR 1 ;

R 1 is a radical selected from the group consisting of: C 4-7 saturated heterocycle containing at least one heteroatom selected from O, N, and S wherein the said heterocycle is optionally substituted, and the free ring N atom may optionally take a substituent; or a deuterated compound of any such compound.

2. A compound as recited in claim 1 , wherein the radical R 3 is optionally substituted with one or two substituents independently selected from the following: lower alkyl, amino, substituted amino, carboxamide.

3. A compound as recited in claim 1 , which is selected from the following group of compounds:

and pharmaceutically acceptable salts of such compounds, and deuterated compounds of such compounds and salts.

4. A compound of formula (I) as defined in claim 1 , wherein the compound is selected from the group consisting of:

(2S,5R)-7-oxo-N(pyrrolidin-3-yloxy)-6-(sulfooxy)-1,6-diazabicyclo[3.2.1]octane-2-carboxamide

(2S,5R)—N-[(1-methylpyrrolidin-3-yl)oxy]-7-oxo-6-(sulfooxy)-1,6-diazabicyclo[3.2.1]octane-2-carboxamide

(2S,5R)-7-oxo-N-(piperidin-3-yloxy)-6-(sulfooxy)-1,6-diazabicyclo[3.2.1]octane-2-carboxamide

(2S,5R)-7-oxo-N-(pyrrolidin-2-ylmethoxy)-6-(sulfooxy)-1,6-diazabicyclo[3.2.1]octane-2-carboxamide

(2S,5R)-7-oxo-N-(piperidin-2-ylmethoxy)-6-(sulfooxy)-1,6-diazabicyclo[3.2.1]octane-2-carboxamide

(2S,5R)-7-oxo-N-(piperidin-3-ylmethoxy)-6-(sulfooxy)-1,6-diazabicyclo[3.2.1]octane-2-carboxamide

(2S,5R)—N-[(5-carbamoylpyrrolidin-3-yl)oxy]-7-oxo-6-(sulfooxy)-1,6-diazabicyclo[3.2.1]octane-2-carboxamide

or a deuterated compound of any such compound.

5. A pharmaceutical composition containing as an active ingredient, at least one compound as recited in claim 1 .

6. A molecular complex comprising a compound as recited in claim 1 and at least one solvent.